Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress

Navy Aegis Ballistic Missile Defense (BMD)

Program: Background and Issues for Congress

Updated January 20, 2026

Congressional Research Service

https://crsreports.congress.gov

RL33745

SUMMARY

Navy Aegis Ballistic Missile Defense (BMD)

Program: Background and Issues for Congress

RL33745

January 20, 2026

Ronald O'Rourke

Specialist in Naval Affairs

The Aegis ballistic missile defense (BMD) program, which is carried out by the Missile Defense

Agency (MDA) and the Navy, gives Navy Aegis cruisers and destroyers a capability for

conducting BMD operations. BMD-capable Aegis ships operate in European waters to defend

Europe from potential ballistic missile attacks from countries such as Iran, and in in the Western

Pacific and the Persian Gulf to provide regional defense against potential ballistic missile attacks

from countries such as China, North Korea, and Iran. The number of BMD-capable Aegis ships has been growing over time.

MDA’s FY2026 budget submission states that “by the end of FY 2026, there will be 63 total BMD capable [Aegis] ships

requiring maintenance support.”

The Aegis BMD program is funded to a large degree through MDA’s budget. The program has presented multiple potential

oversight issues for Congress. Congress’s decisions on the Aegis BMD program could significantly affect U.S. BMD

capabilities and funding requirements, and the BMD-related industrial base.

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Contents

Introduction ..................................................................................................................................... 1

Background ..................................................................................................................................... 1

Aegis Ships ............................................................................................................................... 1

Ticonderoga (CG-47) Class Aegis Cruisers ........................................................................ 1

Arleigh Burke (DDG-51) Class Aegis Destroyers .............................................................. 1

Aegis Ships in Allied Navies .............................................................................................. 2

Aegis BMD System................................................................................................................... 2

Versions and Capabilities of Aegis BMD System ............................................................... 2

Aegis BMD Interceptor Missiles ........................................................................................ 3

Numbers of BMD-Capable Aegis Ships ................................................................................... 8

BMD-Capable Aegis Destroyers Forward-Homeported in Spain ............................................. 8

Aegis Ashore Sites .................................................................................................................... 9

Two Navy-Operated Sites in Romania and Poland ............................................................. 9

Navy Interest in Divesting Aegis Ashore Sites It Operates............................................... 10

Japan Planned and Later Canceled Two Sites ....................................................................11

Use of Aegis BMD Elements in Guam Missile Defense System ............................................ 12

Aegis BMD Development Philosophy and Flight Tests.......................................................... 13

Allied Participation and Interest in Aegis BMD Program ....................................................... 13

Japan ................................................................................................................................. 13

South Korea ...................................................................................................................... 14

Other Countries ................................................................................................................. 14

Aeigs BMD Program Funding ................................................................................................ 14

Issues for Congress ........................................................................................................................ 15

Annual Funding Request ......................................................................................................... 15

Program Deliveries, Testing, and Technical Risk.................................................................... 15

January 2025 DOT&E Report .......................................................................................... 15

May 2023 GAO Report ..................................................................................................... 15

Inventories of BMD-Capable Interceptor Missiles ................................................................. 18

Potential Contribution from Lasers ......................................................................................... 19

Issues in Earlier Years ............................................................................................................. 20

Estimating and Reporting Costs........................................................................................ 20

Potential for Intercepting ICBMs ...................................................................................... 20

Required vs. Available Numbers of BMD-Capable Aegis Ships ...................................... 23

Burden of BMD Mission on U.S. Navy Aegis Ships ........................................................ 24

Allied Burden Sharing: U.S. vs. Allied Contributions to Regional BMD

Capabilities .................................................................................................................... 27

Conversion of Hawaii Aegis Test Site .............................................................................. 28

Figures

Figure 1. GAO Summary of Capabilities of Aegis BMD System Variants ..................................... 3

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Tables

Table 1. FY2026 MDA Procurement and R&D Funding Line Items for Aegis

BMD Efforts ............................................................................................................................... 14

Table A-1. Reported Aegis BMD Flight Tests From January 2002 to the Present ........................ 30

Appendixes

Appendix. Reported Aegis BMD Flight Tests ............................................................................... 30

Contacts

Author Information........................................................................................................................ 33

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Introduction

This report provides background information and issues for Congress on the Aegis ballistic

missile defense (BMD) program, a program carried out by the Missile Defense Agency (MDA)

and the Navy that gives Navy Aegis cruisers and destroyers a capability for conducting BMD

operations. The issue for Congress is whether to approve, reject, or modify Department of

Defense (DOD) acquisition strategies and proposed funding levels for the Aegis BMD program.

Congress’s decisions on the Aegis BMD program could significantly affect U.S. BMD

capabilities and funding requirements, and the BMD-related industrial base.

Background

Aegis Ships

All but three of the Navy’s cruisers and destroyers are called Aegis ships because they are

equipped with the Aegis ship combat system—an integrated collection of sensors, computers,

software, displays, weapon launchers, and weapons named for the mythological shield that

defended Zeus. (The exceptions are the Navy’s three Zumwalt [DDG-1000] class destroyers,

which are discussed below.) The Aegis system was originally developed in the 1970s for

defending ships against aircraft, anti-ship cruise missiles (ASCMs), surface threats, and

subsurface threats. The system was first deployed by the Navy in 1983, and it has been updated

many times since. The Navy’s Aegis ships include Ticonderoga (CG-47) class cruisers and

Arleigh Burke (DDG-51) class destroyers.

Ticonderoga (CG-47) Class Aegis Cruisers

A total of 27 CG-47s (CGs 47 through 73) were procured for the Navy between FY1978 and

FY1988; the ships entered service between 1983 and 1994. The first five ships in the class (CGs

47 through 51), which were built to an earlier technical standard in certain respects, were judged

by the Navy to be too expensive to modernize and were removed from service in 2004-2005,

leaving 22 ships in operation (CGs 52 through 73). Retirements of these 22 ships began in

FY2022. As of October 1, 2025, seven remained in service. The Navy’s FY2025 budget

submission projected that the final two CG-47s would be retired in FY2027.

Arleigh Burke (DDG-51) Class Aegis Destroyers

The Navy began procuring DDG-51s in FY1985, and a total of 97 have been procured through

FY2025. The first DDG-51 entered service in 1991, and a total of 76 were in service as of

October 1, 2025. Under the Navy’s FY2025 budget submission, retirements of older DDG-51s

were to begin in FY2028.

The DDG-51 design has been updated multiple times over the years. The first 28 DDG-51s are

known as Flight I/II DDG-51s. The next 34, known as Flight IIA DDG-51s, incorporate some

significant design changes, including the addition of a helicopter hangar. The version currently

being procured, called the Flight III DDG-51 design, incorporates another significant change—a

new radar, called the SPY 6 radar (and prior to that, the Air and Missile Defense Radar, or

AMDR), that is more capable than the SPY-1 radar installed on CG-47s and earlier DDG-51s.

No DDG-51s were procured in FY2006-FY2009. The Navy during this period instead procured

the three above-mentioned Zumwalt (DDG-1000) class destroyers. The DDG-1000 design does

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not use the Aegis system and does not include a capability for conducting BMD operations. Navy

plans do not call for modifying the three DDG-1000s to make them BMD-capable.1

Aegis Ships in Allied Navies

Sales of the Aegis system to allied countries began in the late 1980s. Allied countries that now

operate, are building, or are planning to build Aegis-equipped ships include Japan, South Korea,

Australia, Spain, and Norway.2 Japan’s Aegis-equipped ships are BMD-capable. An October 16,

2023, press report states that South Korea’s newest Aegis destroyer will be BMD-capable.3 The

Aegis-equipped ships operated by Australia, Spain, and Norway are currently not BMD-capable.

Aegis BMD System4

Aegis ships are given a capability for conducting BMD operations by incorporating changes to

the Aegis system’s computers and software, and by arming the ships with BMD interceptor

missiles. Older Aegis ships can be modified to become BMD-capable ships, and DDG-51s

procured in FY2010 and subsequent years have been built from the start with a BMD capability.

Versions and Capabilities of Aegis BMD System

Overview

The Aegis BMD system exists in multiple variants whose ascending numerical designations

indicate ascending levels of capability. As part of MDA’s FY2022 budget submission, the

designations of Aegis BMD system variants were changed and consolidated to 4.X, 5.X, and 6.X,

with the X indicating multiple subvariants. (The 4.X variant, for example, includes the 4.1 and

4.2 subvariants.)

BMD system variants correlate with certain versions (i.e., baselines, or BLs) of the overall Aegis

system, which have their own numbering system. The more recent BMD variants, in addition to

being able to address more challenging BMD scenarios, give BMD-equipped ships a capability to

simultaneously perform both BMD operations against ballistic missiles and anti-air warfare

(AAW) operations (aka air-defense operations) against aircraft and anti-ship cruise missiles.

Figure 1 provides a 2019 Government Accountability Office (GAO) summary of the capabilities

of the more recent BMD variants and their correlation to Aegis system baselines as of 2019.

Because Figure 1 was prepared in 2019, it uses the older designations for Aegis BMD system

variants, rather than the new designations that were introduced as part of the MDA’s FY2022

budget submission.

The Aegis BMD system was originally designed primarily to intercept theater-range ballistic

missiles, meaning short-, medium-, and intermediate-range ballistic missiles (SRBMs, MRBMs,

and IRBMs, respectively). In addition to its capability for intercepting theater-range ballistic

missiles, detection and tracking data collected by the Aegis BMD system’s radar might be passed

1 For more on the DDG-51 and DDG-1000 programs, see CRS Report RL32109, Navy DDG-51 and DDG-1000

Destroyer Programs: Background and Issues for Congress, by Ronald O'Rourke.

2 The Norwegian ships are somewhat smaller than the other Aegis ships, and consequently carry a reduced-size version

of the Aegis system that includes a smaller, less-powerful version of the SPY-1 radar.

3 YoungHak Lee, “South Korea’s First KDX III Batch II Aegis Destroyer Started Sea Trials,” Naval News, October 16,

2023.

4 Unless stated otherwise, information in this section is taken from MDA briefings on the Aegis BMD program given to

CRS and CBO analysts.

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to other U.S. BMD systems that are designed to intercept intercontinental ballistic missiles

(ICBMs), which might support intercepts of ICBMs that are conducted by those other U.S. BMD

systems.

Figure 1. GAO Summary of Capabilities of Aegis BMD System Variants

Source: Government Accountability Office, Missile Defense[:] Delivery Delays Provide Opportunity for Increased

Testing to Better Understand Capability, GAO-19-387, June 2019, Table 5 on p. 31.

Aegis BMD Interceptor Missiles

The BMD interceptor missiles used by Aegis ships are the Standard5 Missile-3 (SM-3) and the

SM-6.

SM-3 Midcourse Interceptor

The SM-3 is designed to intercept ballistic missiles above the atmosphere (i.e., exo-atmospheric

intercept), in the midcourse phase of an enemy ballistic missile’s flight. It is equipped with a “hitto-kill” warhead, called a kinetic vehicle, that is designed to destroy a ballistic missile’s warhead

5 The Standard Missile is so named because it was originally developed, decades ago, as a surface-to-air (i.e., air

defense) missile to serve as the common (i.e., standard) successor to the Navy’s then-existing collection of Talos,

Terrier, and Tartar air defense missiles, which were sometimes referred to collectively as the 3-T missiles.

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by colliding with it. The current versions of the SM-3 missile include the SM-3 Block IA, the

SM-3 Block IB, and the SM-3 Block IIA.6

Compared to the Block IA version, the Block IB version has an improved (two-color) target

seeker, an advanced signal processor, and an improved divert/attitude control system for adjusting

its course. Compared to the Block IA and 1B versions, which have a 21-inch-diameter booster

stage at the bottom but are 13.5 inches in diameter along the remainder of their lengths, the Block

IIA version has a 21-inch diameter along its entire length. The increase in diameter to a uniform

21 inches provides more room for rocket fuel, permitting the Block IIA version to have a burnout

velocity (a maximum velocity, reached at the time the propulsion stack burns out) that is greater

than that of the Block IA and IB versions, as well as a larger-diameter kinetic warhead. The

United States and Japan cooperated in developing certain technologies for the Block IIA version,

with Japan funding a significant share of the effort.7

An April 15, 2024, press report stated

For the first time in combat, guided-missile destroyers fired missiles developed to intercept

ballistic missiles during the U.S. response to the Iranian attack on Israel, USNI News has

learned.

USS Arleigh Burke (DDG-51) and USS Carney (DDG-64), in the Eastern Mediterranean,

fired four to seven Standard Missile 3s to intercept Iranian ballistic missiles headed toward

Israeli targets over the weekend, two defense officials confirmed to USNI News on

Monday [April 15]….

Both the destroyers were placed off the coast of Israel as part of the defensive measures

against a Iranian strike in retaliation for an Israeli attack on an Iranian embassy in Syria.8

On April 16, 2024, Secretary of the Navy Carlos Del Toro similarly testified to Defense

subcommittee of the Senate Appropriations Committee that over the previous weekend (i.e., the

weekend of April 13-14), U.S. Navy BMD-capable Aegis ships used SM-3s to counter ballistic

missiles fired from Iran.9 Prior to April 2024, it had been reported that Navy ships operating in

the Red Sea had countered anti-ship ballistic missiles (ASBMs) fired by Houthi forces, but the

weapons used by the Navy ships to counter these ASBMs were not specified.10

6 MDA and Navy plans at one point called for the SM-3 Block IIA to be succeeded by a still-more-capable interceptor

called the SM-3 Block IIB. The effort to develop that missile, however, was ended years ago, and MDA at the time was

reportedly not pursuing any follow-on capabilities to the SM-3 Block IIA. (See, for example, Justin Doubleday,

“Missile Defense Agency Not Pursuing Follow-On to SM-3 Block IIA Interceptor,” Inside the Navy, October 24,

2016.)

7 The cooperative research effort was carried out under a U.S.-Japan memorandum of agreement signed in 1999. The

effort focused on risk reduction for four parts of the missile: the sensor, an advanced kinetic warhead, the second-stage

propulsion, and a lightweight nose cone.

8 Sam LaGrone, “SM-3 Ballistic Missile Interceptor Used for First Time in Combat, Officials Confirm,” USNI News,

April 15, 2024.

9 For press articles about Secretary Del Toro’s testimony, see, for example, Jake Epstein, “US Navy Warships Shot

Down Iranian Missiles with a Weapon They’ve Never Used in Combat Before,” Business Insider, April 16, 2024;

Connor O’Brien, “Nearly $1B in Missiles Used in Middle East, Navy Secretary Says,” Politico Pro, April 16, 2024.

See also Jake Epstein, “A U.S. Navy Missile That Just Scored Its First Kill This Year Got Another Workout Against

Iranian Weapons,” Business Insider, October 3, 2024; Mallory Shelbourne and Sam LaGrone, “U.S. Destroyers

Successfully Down Iranian Missiles with SM-3s, Carrier USS Harry. S. Truman Now in U.S. 6th Fleet,” USNI News,

October 2, 2024.

10 See, for example, Jake Epstein, “US Warships Are Shooting Down Weapons No One’s Ever Faced in Combat

Before, and a Navy Commander Says it’s a ‘Great Opportunity,’” Business Insider, February 17, 2024. See also Tom

Sharpe, “History Has Been Made as Ballistic Missiles Finally Used against Warships for Real,” Telegraph (UK),

February 16, 2024.

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A March 31, 2020, press report stated

Raytheon and the Missile Defense Agency are exploring options to extend the range of the

Standard Missile-3 Block IB—pushing the ballistic missile interceptor to dramatically

expand a defended area by allowing the weapon to communicate with off-board radars—a

move that would require enhancing one of the Aegis ballistic missile defense system’s

newest features: Engage-on-Remote….

MDA Director Vice Adm. Jon Hill told Congress earlier this month that the new Engageon-Remote capability provides “a seven-fold increase in missile defense coverage when

compared to an autonomous Aegis platform.”11

SM-6 Terminal Interceptor (Overview)

The SM-2 Block IV was MDA’s and the Navy’s initial sea-based terminal-phase (SBT) BMD

interceptor. It was designed to intercept ballistic missiles inside the atmosphere (i.e., endoatmospheric intercept), during the terminal phase of an enemy ballistic missile’s flight. It was

equipped with a blast fragmentation warhead. A limited number of these missiles were produced

years ago.12 The SM-2 Block IV has now been replaced by the SM-6.

The SM-6 is MDA’s and the Navy’s more capable next-generation SBT BMD interceptor. It is

based on the SM-6 air defense missile (the Navy’s successor to the SM-2 air defense missile).

The SM-6 is a dual-capability missile that can be used for either air defense (i.e., countering

aircraft and ASCMs) or ballistic missile defense. A July 23, 2018, press report states the

following:

The Defense Department has launched a prototype project that aims to dramatically

increase the speed and range of the Navy’s Standard Missile-6 by adding a larger rocket

motor to the ship-launched weapon, a move that aims to improve both the offensive and

defensive reach of the Raytheon-built system.

On Jan. 17 [2018], the Navy approved plans to develop a Dual Thrust Rocket Motor with

a 21-inch diameter for the SM-6, which is currently fielded with a 13.5-inch propulsion

package. The new rocket motor would sit atop the current 21-inch booster, producing a

new variant of the missile: the SM-6 Block IB.13

SM-6 Terminal Interceptor (Hypersonic Threat Intercept Capability)

MDA and the Navy are developing a capability for the SM-6 to intercept hypersonic missiles.

MDA testified in December 2023 that

Today, the SM-6, which uses a blast fragmentation kill mechanism, is the only interceptor

available for a limited defense against hypersonic missile threats….

MDA is working closely with the Navy to develop, field, and upgrade SBT defenses to

counter more advanced maneuvering and hypersonic threats. SBT Inc 2 is deployed. MDA

is analyzing the evasion maneuvers that hypersonic weapons may perform and addressing

them in Aegis SBT Inc 3. SBT Inc 3 upgrade and delivery are in 2025 and include terminal

11 Jason Sherman, “After MDA Demonstrates 7x Increase in Defended Area, Raytheon Pitching EOR for Older SM-

3s,” Inside Defense, March 31, 2020.

12 The inventory of SM-2 Block IVs was created by modifying SM-2s that were originally built to intercept aircraft and

ASCMs. A total of 75 SM-2 Block IVs were modified, and at least 3 were used in BMD flight tests through February

2012.

13 Jason Sherman, “Navy Looking to Increase Range, Speed of SM-6 with Larger Rocket Motor,” Inside the Navy, July

23, 2018.

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defense capability against hypersonic threats. MDA will conduct flight tests against

advanced threat-representative targets in FY 2024 and FY 2025….

Additionally, MDA is working closely with the Navy to develop, field, and upgrade SBT

defenses to counter more advanced maneuvering and hypersonic threats. We anticipate

delivering these SBT Inc 3 capabilities in 2025. We are also engaged in a competitive

development effort to significantly enhance hypersonic missile defense capabilities. MDA

is developing a layered defense capability against regional hypersonic threats and have

initiated a development program for Glide Phase Intercept (GPI) to defend the sea-base

and regional forces ashore, leveraging existing systems where possible, including proven

engage-on-remote and launch-on-remote capabilities. Layered defenses provide more

opportunities to engage and potentially neutralize hypersonic threats in-flight. We are

focusing on the proven Aegis Weapon System to provide the depth-of-fire needed for a

layered defense against hypersonic threats. Today, MDA is funding technology maturation

of two GPI concepts on the path to preliminary design.

The Aegis Sea-Based GPI, planned for delivery in 2034, includes the ability to plan, detect,

track, and defeat threats, and support integrated layered multiple engagement

opportunities. GPI is developing a missile and updates to the existing Aegis Weapon

System to counter hypersonic threats. The GPI interceptor will be hypersonic, multistage,

and compatible with the Navy’s MK-41 Vertical Launch System. MDA also is pursuing a

Cooperative Development of the GPI Interceptor with the Japan Ministry of Defense. This

project will focus on interceptor updates, and the United States will be responsible for the

overall missile system design and integration. Japan will fund and develop all Japan

workshare elements (to include rocket motor assemblies and control systems).14

In September 2024, it was reported that MDA had selected Northrop Grumman to design the

GPI.15

A March 25, 2025, MDA news release states

The Missile Defense Agency, in cooperation with the U.S. Navy, successfully executed

Flight Test Other-40 (FTX-40), or Stellar Banshee, on March 24, 2025. In doing so, the

agency achieved a significant step in advancing defenses to counter hypersonic threats to

operational forces and the nation.

During the test, conducted off the coast of the Pacific Missile Range Facility, Kauai,

Hawaii, USS Pinckney (DDG 91) demonstrated the ability to detect, track and perform a

simulated engagement of an advanced maneuvering hypersonic target using the Sea Based

Terminal (SBT) Increment 3 capability embedded in the latest Aegis software baseline.

The tracking exercise included firing a simulated Standard Missile (SM)-6 upgraded

missile at the target, an air-launched Medium Range Ballistic Missile (MRBM) with a

Hypersonic Target Vehicle (HTV) - 1 front end. This target is engineered to allow testing

and defeat of a variety of hypersonic threats. FTX-40 also provided a data collection

opportunity for the Hypersonic and Ballistic Tracking Space Sensor (HBTSS)

demonstration satellite.

“Our ability to defeat maneuvering, hypersonic missiles is critical if we are to defend our

homeland and our forces against an increasingly dangerous threat,” said MDA Director Lt.

Gen. Heath Collins. “The Aegis Weapon System will play a vital role in the nextgeneration integrated air and missile defense system, and today’s test demonstrated key

14 [Statement of] Rear Admiral Douglas L. Williams, USN, Director (Acting), Missile Defense Agency, Before the

House Armed Services Committee, Strategic Forces Subcommittee, December 7, 2023, [hearing on] Demand for

Theater Missile Defense Assets, pp. 4, 6, 7-8. See also Rich Abott, “MDA Still Trying To Quicken Hypersonic

Defense, SM-6 Increment Three To Increase Hypersonic Targeting,” Defense Daily, August 12, 2024.

15 Jen Judson, “Pentagon Makes Early Pick for Hypersonic Interceptor Developer,” Defense News, September 26, 2024.

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achievements as we continue to partner with the Navy in advancing our Nation’s counterhypersonic capabilities.”

This test was another successful example of the integration of space capabilities passing

data that was processed through fire control and then provided to the ship for their

simulated Aegis engagement of the target. Data analysis from this test could help inform

efforts to advance the Nation’s counter-hypersonic and missile defense capabilities.

FTX-40 served as a key risk reduction flight for the new MDA-developed test target and a

data collection opportunity for the Aegis baseline against a hypersonic representative

target. This exercise is a building block for a live intercept of the MRBM HTV-1 target

using the upgraded SM-6. That planned test is known as Flight Test Aegis Weapon System43 (FTM-43).

FTX-40 builds on the success of FTM-32, an SBT Increment 3 flight test experiment,

which was conducted last year and demonstrated the capability of an Arleigh Burke-class

destroyer to detect, track, engage and intercept an MRBM target in the terminal phase of

flight with an SM-6.16

Patriot (PAC-3 MSE) Interceptor (Hypersonic Threat Intercept Capability)

An October 25, 2024, press report states

Fearing China will deploy hypersonic weapons to sink ships in the Pacific, the U.S. Navy

is moving forward with a plan to arm some of its vessels with Patriot interceptor missiles,

two senior defense officials said.

One industry official said putting the highly agile Patriot Advanced Capability-3 Missile

Segment Enhancement (PAC-3 MSE) interceptors, used primarily in the U.S. by the Army,

aboard Navy ships anticipates advances in Chinese missile technology, including the use

of highly maneuverable hypersonic weapons.

Integrating the Lockheed Martin-made… missiles with ships' air defenses comes amid

simmering tension in the Indo-Pacific region as China rapidly modernizes its military, and

in the wake of successful missile defense efforts in Ukraine and the Middle East….

The PAC-3 is shorter-ranged than the Navy's SM-6 missiles and cannot reach into space.

But steering rockets near the nose make it more agile, and destruction of the threat is more

likely because of its "hit to kill" concept, in which the interceptor strikes the target rather

than explode near it, said a missile defense program director with direct knowledge of the

Aegis system.

Facing advanced Chinese weapons, including hypersonic glide vehicle warheads, those

qualities "supplement the existing missiles on a U.S. ship very well" by being able to more

easily hit high-speed, maneuvering ballistic missiles and destroy them, said the program

director….

A PAC-3 interceptor from a Patriot missile system, primarily used by the U.S. Army and

allied nations for land-based air defense, was tested in May on a "virtual Aegis ship" using

a Mk. 70 vertical launcher, but has not been deployed on naval vessels.

In the last year, however, it has intercepted numerous ballistic threats and aircraft in the

Middle East and Ukraine, including Russia's advanced Khinzal missiles, making it an

16 Missile Defense Agency, “MDA and Navy Accomplish Next Step in Hypersonic Missile Defense,” news release 25-

NEWS-0002, March 25, 2025. See also Joseph Trevithick, “SM-6 Missile Closer To Proving Hypersonic Weapon

Intercept Capability After Aegis Destroyer Test,” The War Zone, March 27, 2025; Rich Abott, “MDA And Navy Test

Aegis Against Hypersonic Target,” Defense Daily, March 25, 2025; Jason Sherman, “MDA, Navy Execute Key Test of

Hypersonic Defense Capabilities with Aegis and New Target,” Inside Defense, March 25, 2025.

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attractive addition to Navy magazines, the defense officials and people familiar with the

matter said.

The PAC-3 round is also much smaller than an SM-6 or SM-3, weighing about 300 kg (660

lbs), compared with 1,500 kg for the SM-6, and is about 9 cm (3.5 inches) smaller in

diameter.

Cost per missile varies by the customer and the deal, but both are roughly $4 million each,

according to estimates.17

Numbers of BMD-Capable Aegis Ships

The number of BMD-capable Aegis ships has been growing over time. MDA’s FY2025 budget

submission states: “By the end of FY 2026, there will be 63 total BMD capable ships requiring

maintenance support.”18

BMD-Capable Aegis Destroyers Forward-Homeported in Spain

On October 5, 2011, the United States, Spain, and NATO jointly announced that four BMDcapable U.S. Navy Aegis destroyers were to be forward-homeported (i.e., based) at the naval base

at Rota, Spain.19 The initial set of four ships was transferred to Rota in FY2014 and FY2015.20

They were replaced at Rota by a new set of four BMD-capable U.S. Navy Aegis destroyers in

2020-2022.21

Navy officials said the four Rota-based ships can provide a level of level of presence in the

Mediterranean for performing BMD patrols and other missions equivalent to what could be

provided by about 10 BMD-capable Aegis ships that are homeported on the U.S. east coast, thus

effectively releasing about six U.S. Navy BMD-capable Aegis ships for performing BMD patrols

or other missions elsewhere.

In February and March 2020, DOD officials testified that DOD was considering forwardhomeporting an additional two BMD-capable Aegis destroyers at Rota, which would make for a

17 Mike Stone and Gerry Doyle, “Fearing China's Hypersonic Weapons, US Navy Seeks to Arm Ships with Patriot

Missiles,” Reuters, October 25, 2024. See also “US Navy Eyes Patriot Missiles to Counter China’s Hypersonic Threats

in Pacific,” Army Recognition Group, October 25, 2024.

18 Missile Defense Agency, Fiscal Year 2026 Budget Estimates, Missile Defense Agency, June 2025, p. 14. (This is the

FY2026 budget justification book for MDA’s portion of the Operation and Maintenance, Defense-Wide appropriation

account.)

19 “Announcement on missile defence cooperation by NATO Secretary General Anders Fogh Rasmussen, the Prime

Minister of Spain, Jose Luis Rodriguez Zapatero and US Defense Secretary Leon Panetta,” October 5, 2011, accessed

May 18, 2022, at http://www.nato.int/cps/en/SID-107ADE55-FF83A6B8/natolive/opinions_78838.htm. See also

“SECDEF Announces Stationing of Aegis Ships at Rota, Spain,” accessed May 18, 2022, at https://web.archive.org/

web/20120117065346/http:/www.navy.mil/search/display.asp?story_id=63109.

Rota is on the southwestern Atlantic coast of Spain, a few miles northwest of Cadiz, and about 65 miles northwest of

the Strait of Gibraltar leading into the Mediterranean. U.S. Navy ships have been homeported at Rota at various points

in the past, most recently (prior to the current arrangement) in 1979. (Source: Sam Fellman, “U.S. To Base AntiMissile Ships in Spain,” Defense News, October 10, 2011: 76.)

20 The four ships were the destroyers Ross (DDG-71) and Donald Cook (DDG-75), which moved to Rota in FY2014,

and the destroyers Carney (DDG-64) and Porter (DDG-78), which moved to Rota in FY2015.

21 See, for example, Mallory Shelbourne, “USS Arleigh Burke Arrives in Spain, USS Donald Cook Will Head to

Mayport,” USNI News, April 12, 2021.

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total of six destroyers at the site.22 Navy officials testified in 2020 that they supported the idea.23

On June 28, 2022, the Biden Administration announced that two additional Aegis destroyers

would be homeported at Rota.24 The Navy confirmed that the two additional Aegis destroyers are

to be BMD-capable.25 An October 24, 2022, press report stated that “the U.S. and Spain will soon

launch negotiations on a new defense pact for an expanded naval presence in Spain,” including

the two additional BMD-capable Aegis destroyers. The report stated that “while an official

timeline for the ships’ arrival in Spain hasn’t been set, U.S. military commanders have put 2025

or 2026 as target years.”26 On May 8, 2023, Spain and the United States reportedly signed the

new agreement.27 The first of the two additional ships reportedly arrived at Rota in October

2024.28 The second additional ship reportedly is scheduled to arrive in 2026.29

Aegis Ashore Sites

Two Navy-Operated Sites in Romania and Poland

The land-based version of the Aegis BMD system is called Aegis Ashore. There are two Aegis

Ashore sites, both in Europe—one in Romania, and one in Poland. The sites are intended to help

defend Europe against ballistic missile threats from countries such as Iran. Each Aegis Ashore site

includes a structure housing an Aegis system that is similar to the deckhouse on an Aegis ship,

and 24 SM-3 missiles launched from a relocatable Vertical Launch System (VLS) based on the

VLS that is installed in Navy Aegis ships.30

The plan to establish the two Aegis Ashore sites in Romania and Poland was announced in 2009,

as part of a plan for providing regional BMD defense in Europe called the European Phased

Adaptive Approach (EPAA). The Aegis Ashore site in Romania achieved operational certification

22 See, for example, Paul McCleary, “EUCOM Calls For Two More Ships For Spanish Port,” Breaking Defense,

February 25, 2020; David B. Larter, “Push to Base Six US Navy Destroyers in Spain Could Be Gaining Steam,”

Defense News, March 3, 2020.

23 See, for example, David B. Larter, “The US Navy’s Top Officer Declares Support for Basing 6 Destroyers in Spain,”

Defense News, March 5, 2020. See also John Vandiver, “Rota to Gain Two US Destroyers by Middle of the Decade,

EUCOM Chief Says,” Stars and Stripes, April 15, 2021.

24 White House, “Press Gaggle by Press Secretary Karine Jean-Pierre and National Security Advisor Jake Sullivan En

Route Madrid, Spain,” June 28, 2022. See also Mallory Shelbourne, “Biden Administration Basing Two More

Destroyers in Rota, Spain,” USNI News, June 28 (updated June 29), 2022; Justin Katz, “‘A Powerful Signal:’ What It

Means to Send Two More DDGs to Spain,” Breaking Defense, July 1, 2022; Aaron Mehta, “US Increasing Troop

Presence in Europe, While New NATO Strategy Eyes China,” Breaking Defense, June 29, 2022; Geoff Ziezulewicz

(Associated Press), “Two More Navy Destroyers Will Be Homeported in Rota, Spain,” Navy Times, June 29, 2022.

25 Source: Navy Office of Legislative Affairs email to CRS, July 1, 2022.

26 John Vandiver, “Talks on Addition of 2 Navy Destroyers at Base in Spain Expected to Start Soon,” Stars and

Stripes, October 24, 2022.

27 Heather Mongilio, “U.S., Spain Agree to Host Two More Warships in Rota,” USNI News, May 9, 2023.

28 Alison Bath, “USS Oscar Austin Arrives at New Homeport in Spain, Boosting Missile Defense in Europe,” Stars and

Stripes, October 16, 2024.

29 Alison Bath, “Fifth US Navy Destroyer Expected to Arrive in Spain This Fall,” Stars and Stripes, August 16, 2024.

30 For additional discussion of the Aegis Ashore sites, see Edward Lundquist, “Aegis Ashore Adapts Sea-Based Missile

Defense System to Protect Europe,” National Defense, September 2016.

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in May 2016.31 The site in Poland began construction in May 201632 and was initially scheduled

to be completed in 2018. Its completion, however, was delayed for years by construction

contractor performance issues.33 At a December 7, 2023, hearing on regional missile defense

assets before the Strategic Forces subcommittee of the House Armed Services Committee, Rear

Admiral Douglas L. Williams, the acting director of MDA, testified that

Aegis Ashore Poland, located in Redzikowo, was added to the Operational Capability

Baseline in September 2023 with upgrades over the original design and state-of-the-art

Integrated Electronic Security System. Aegis Ashore Poland was delivered to the U.S.

Navy on October 1, 2023 for operational use and maintenance. The Navy will formally

accept Aegis Ashore Poland into their inventory on December 15, 2023. This will complete

EPAA Phase 3, originally established in 2009. The Navy will install additional upgrades

at Aegis Ashore Poland through May 2024, after which it will transfer to NATO in July

2024 for command and control of Aegis Ashore Poland in the defense of NATO European

states against ballistic missile threats originating outside the Euro-Atlantic area.34

On July 10, 2024, the Aegis Ashore site in Poland was declared mission-ready by NATO.35 The

site reportedly was officially activated on November 13, 2024.36

Navy Interest in Divesting Aegis Ashore Sites It Operates

On January 11, 2021, the Chief of Naval Operations (CNO), Admiral Michael Gilday, released a

guidance document for the Navy entitled CNO NavPlan (with NavPlan being short for navigation

plan) that states

To remain ahead of our competitors, we will divest ourselves of legacy capabilities that no

longer bring sufficient lethality to the fight. This includes divestment of experimental

Littoral Combat Ship hulls, legacy Cruisers, and older Dock Landing Ships. It also includes

divesting non-core Navy missions like Aegis-ashore. Transferring shore-based Ballistic

Missile Defense sites to ground forces enables Sailors to focus on their core missions at

sea and frees up resources to increase our lethality.37

31 See, for example, Amy Forsythe, “U.S. Navy Aegis Ashore Base in Romania Hosts NATO Country Ambassadors,”

Defense Visual Information Distribution Service (DVIDS), November 19, 2019; “Aegis Ashore,” Missile Defense

Advocacy Alliance, accessed May 18, 2022, at https://missiledefenseadvocacy.org/defense-systems/aegis-ashore/; US

Naval Forces Europe-Africa, “Aegis Ashore Missile Defense System (AAMDS)-Romania Operationally Certified,”

Defense-Aerospace.com, May 12, 2016.

32 See, for example, “Aegis Ashore,” Missile Defense Advocacy Alliance, accessed May 18, 2022, at

https://missiledefenseadvocacy.org/defense-systems/aegis-ashore/.

33 Source: [Statement of] Vice Admiral Jon A. Hill, USN, Director, Missile Defense Agency, Before the Senate Armed

Services Committee, Strategic Forces Subcommittee, May 18, 2022, p. 8. Earlier reporting said construction of the

Poland site would be complete by the end of 2022. See, for example, Rich Abott, “Aegis Ashore Poland Set To Be

Operational By End Of 2022,” Defense Daily, November 22, 2021; Jen Judson, “Construction of Aegis Ashore in

Poland Nearing Completion,” Defense News, March 9, 2022. See also Daniel Wasserbly, “US MDA Plans to Turn On

Polish Aegis Ashore Site in June, After Years of Delay,” Jane’s Defence Weekly, May 24, 2022.

34 [Statement of] Rear Admiral Douglas L. Williams, USN, Director (Acting), Missile Defense Agency, Before the

House Armed Services Committee, Strategic Forces Subcommittee, December 7, 2023, [on] Demand for Theater

Missile Defense Assets, pp. 3-4. See also Jason Sherman, “After ‘Grossly Unacceptable Delay,’ Aegis Ashore Poland

Set for Navy Inventory, Maintenance,” Inside Defense, December 7, 2023; Joseph Trevithick, “Aegis Missile Defense

Site In Poland To Finally Go Operational (Updated),” The Drive, December 7, 2023.

35 John Vandiver, “US Navy Missile Defense Site in Poland Is Mission-Ready, NATO Says,” Stars and Stripes, July

11, 2024.

36 Jaroslaw Adamowski, “NATO Activates Poland Antimissile Site, as Warsaw Ups Ammo Production,” Defense

News, November 20, 2024.

37 U.S. Navy, Chief of Naval Operations, CNO NavPlan, January 2021, p. 10. See also Richard R. Burgess, “CNO:

Divest Aegis Ashore Sites to Ground Forces,” Seapower, January 11, 2021.

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A January 12, 2021, press report states

The chief of naval operation’s new call to focus on sea control and power projection could

lead the service to shed other non-core missions the Navy conducts today, such as manning

Aegis Ashore missile defense sites.

The biggest problem is, no one else has agreed to take over that mission yet….

… no one else operates Aegis systems today, and no one has yet agreed to take over Aegis

Ashore, Rear Adm. Paul Schlise, the director of surface warfare on the CNO’s staff

(OPNAV N96), said today during a panel presentation at the Surface Navy Association’s

annual symposium.

“It’s been an ongoing discussion in the building here. Right now we’ve got the Aegis

Ashore sites in Europe, and there’s discussions about potentially more sites in other places.

The general discussion has been, this is not a core Navy mission. Sailors really belong at

sea serving in ships. And we’ve got a good number of highly qualified folks serving in

those sites, they’re going a great job,” he said.

“But I think what the CNO teed up is, is this a core Navy mission? I don’t think it is. And

so there’s been some discussion with the Army. The Army, of course, has some missile

defense capability and of course great soldiers that serve in those roles. But they don’t have

any experience with that [Aegis Combat System], the systems that have been installed or

are in progress in Romania and Poland. So that’s been a running discussion.”

Schlise said the discussion is taking place at the Office of the Secretary of Defense level.

Without any final decisions, though, the Navy could not shed Aegis Ashore spending in its

most recent budgeting work, the Fiscal Year 2022 request that will come out after the Biden

administration comes in and can review it.

“For the purposes of this past budget cycle, it was just kind of tabled. So we’ll have to see

where that discussion goes. As always, here in the building, it’s about money. So if that

transition were to be considered and approved for moving forward, to transition it to

another service, ‘who’s going to pay’ will of course be part of the discussion,” Schlise

said.38

Japan Planned and Later Canceled Two Sites

Prior to June 2020, Japan had planned to procure and operate two Aegis Ashore systems.39 The

two systems reportedly were to have been equipped with a new Lockheed-made radar called the

Long Range Discrimination Radar (LRDR) rather than the Raytheon-made SPY-6 AMDR that is

being installed on U.S. Navy Flight III DDG-51s, and reportedly were to go into operation by

2023.40 On June 15, 2020, however, Japan announced that it had suspended implementation of its

Aegis Ashore initiative due to cost growth and technical concerns.41 On June 25, 2020, Japan

38 Megan Eckstein, “Navy Wants to Shed Aegis Ashore Mission, But Army Still Hasn’t Agreed to Take It,” USNI

News, January 12, 2021.

39 Yomiuri Shimbun, “Akita, Yamaguchi to Get Aegis Ashore/GSDF Involvement Expected to Strengthen Missile

Defense,” The Japan News, November 11, 2017. See also Kyodo, “Japan Mulling News Missile Interceptor

Deployment to Guard Against North Korea,” South China Morning Post, November 11, 2017.

40 Anthony Capaccio, “Japan in Talks With U.S. on Buying Aegis Missile Defense,” Bloomberg, November 7, 2017.

41 See, for example, Rich Abott, “Japan Suspends Aegis Ashore Due To Technical And Cost Concerns,” Defense Daily,

June 15, 2020; Sam LaGrone, “Japan Backing Away From Aegis Ashore,” USNI News, June 15, 2020; Mari

Yamaguchi, “Japan to Scrap Costly Land-Based US Missile Defense System,” Associated Press, June 15, 2020; Mike

Yeo, “Japan Suspends Aegis Ashore Deployment, Pointing to Cost and Technical Issues,” Defense News, June 15,

2020; Brad Glosserman, “Canceling Aegis Ashore Raises Problems—and Hopes,” Japan Times, June 17, 2020.

Prior to the June 15, 2020, announcement, Japan had announced in early May that it would evaluate alternatives to the

(continued...)

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confirmed that it had canceled the plan for deploying the two Aegis Ashore sites. Rather than

building the two Aegis Ashore systems, Japan is instead building two additional BMD-capable

Aegis ships.42 The two ships reportedly are scheduled to enter service in March 2028 and March

2029.43 A June 23, 2023, press report stated that once the two additional BMD-capable Aegis

ships go into service, Japan’s other eight BMD-capable destroyers will revert to anti-air-warfare

(AAW) operations.44

Use of Aegis BMD Elements in Guam Missile Defense System

After studying various possible BMD system architectures for Guam, DOD proposed a system

combining elements of the Aegis BMD system with elements of Army BMD systems. A March

30, 2022, press report states

The Missile Defense Agency’s initial plan for the architecture to protect Guam turns to

proven systems to help the agency meet a 2026 fielding deadline, according Vice Adm.

Jon Hill, the agency’s director.

The defense of Guam from potential ballistic, cruise and hypersonic missile attacks has

become a priority for the MDA, which is seeking $539 million in fiscal 2023 to continue

to design and develop multiple-land based radar systems, procure weapon system

components and initiate military construction planning and design activity.

“Current forces are capable of defending Guam against today’s North Korean ballistic

missile threats,” Dee Dee Martinez, the MDA’s comptroller said in a March 28 Pentagon

budget briefing. “However, the regional threat to Guam, including from China, continues

to rapidly evolve.”...

The architecture will not be a fixed missile defense site like Aegis Ashore in Romania and

Poland, Hill said. “Think of it as a distributed system.” He added that the agency is

interested in using mobile launchers.

The architecture will include Navy SM-3 and SM-6 missiles, the Patriot air-and-missile

defense system and the Army’s Terminal High Altitude Area Defense System (THAAD).

A THAAD battery has been operating on Guam since 2013.

Those elements will be connected through the Army’s Integrated Battle Command System,

a command-and control-system that connects sensors and shooters on the battlefield. The

agency will also use the Aegis weapon system’s fire control capability, Hill said.

“Patriot [has] a fabulous capability for cruise missile defense, and that’s our first focus

area,” Hill said. “And we have the ability within Aegis to enable that, but, right now, we

are doing ballistic missiles, hypersonic, on the Aegis part of that overall integrated

architecture and then the cruise missile piece will be with the Army systems.”

While MDA is focused on using existing technology to make up the architecture, it will

consider new technology, including the Mid-Range Capability missile the Army will field

in FY23, as it becomes available, according to Hill....

Akita Prefecture site due to strong local opposition to that site. (Masaya Kato, “Japan’s Missile Shield Deployment

Scuppered by Local Resistance,” Nikkei Asian Review, May 7, 2020.)

42 See, for example, Dzirhan Mahadzir, “Japan Locks in Funding for 2 New Aegis Destroyers,” USNI News, December

20, 2023; Thomas Newdick, “Japan’s Missile Defense Ships Will Now Be Multi-Role, Cruiser-Like,” The Drive,

August 31, 2023; Yoshihiro Inaba, “Japan’s New ASEV Ships Will Boast An Impressive 128 VLS Cells,” Naval News,

June 3, 2023.

43 Megan Eckstein, “SPY-7 Radar Tracks Live Space Objects Ahead of Delivery to Japan,” Defense News, April 12,

2024.

44 Ridzwan Rahmat, “Japan to Revert Aegis Destroyers for Air-Defence Roles Once BMD Ships Come Online,” Janes

Defence Weekly, June 23, 2023.

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“That topology of the island … it is a tough place,” Hill said. “An Aegis Ashore site is

limited in what it can do because of the the rise and the fall of the hills, you got radar, it’s

not a flat earth, and it’s certainly not flat on Guam, so we’ve done some really incredible

work and analysis over the last couple years ... by dispersing the systems and making sure

everything’s networked.”45

Aegis BMD Development Philosophy and Flight Tests

The Aegis BMD development effort, including Aegis BMD flight tests, has been described as

following a development philosophy long held within the Aegis program office of “build a little,

test a little, learn a lot,” meaning that development is done in manageable steps, with each step

being tested and validated before moving on to the next step.46 For a summary of reported Aegis

BMD flight tests from 2002 to early 2024, see Table A-1 in the Appendix.

Allied Participation and Interest in Aegis BMD Program

Japan

Eight BMD-Capable Aegis Destroyers

Japan operates eight BMD-capable Aegis destroyers—the eighth was commissioned into service

in March 2021.47 As mentioned above, rather than building two Aegis Ashore systems, Japan is

building two additional BMD-capable Aegis ships that are scheduled to enter service in March

2028 and March 2029, at which point Japan’s other eight BMD-capable destroyers reportedly will

revert to anti-air-warfare (AAW) operations. Japanese BMD-capable Aegis ships have

participated in some of the flight tests of the Aegis BMD system using the SM-3 interceptor (see

Table A-1 in Appendix).

Cooperative Development of SM-3 Block IIA Missile

As mentioned earlier, Japan cooperated with the United States on development the SM-3 Block

IIA missile. Japan developed certain technologies for the missile, and paid for the development of

those technologies, reducing the missile’s development costs for the United States. A July 6,

2018, press report states that “the U.S. and Japan are looking to jointly develop next-generation

45 Jen Judson, “MDA’s Plan to Protect Guam Relies on Field-Proven Systems,” Defense News, March 30, 2022. See

also Thomas Newdick and Tyler Rogoway, “Our First Look At Land-Based Aegis Missile Defense System In Guam,”

The War Zone, October 21, 2024; Robert Peters, The Plan to Defend Guam from Missile Threats Is Years from

Completion: More Investment Is Needed Now, Heritage Foundation, January 9, 2024, 7 pp.; Jason Sherman, “OMB

Reveals Land-Based VLS Also Part of New Guam Missile Defense Architecture,” Inside Defense, July 13, 2022; Rich

Abott, “MDA Decides On Guam Defense Architecture,” Defense Daily, March 29, 2022; Jason Sherman, “DOD Picks

SPY-7 for Land-Based Aegis, Giving Lockheed First U.S. Customer for New Radar,” Inside Defense, May 6, 2022.

46 See, for example, “Aegis BMD: “Build a Little, Test a Little, Learn a Lot,” USNI blog, March 15, 2010, accessed

May 18, 2022, at http://blog.usni.org/2010/03/15/aegis-bmd-build-a-little-test-a-little-learn-a-lot, and “Aegis Ballistic

Missile Defense, Aegis Ballistic Missile Defense Overview for the George C. Marshall Institute, RADM Alan B.

Hicks, USN, Aegis BMD Program Director, August 3, 2009, slide 16 of 20, entitled “Some of our Philosophies In a

Nutshell (1 of 2),” accessed May 18, 2022, at https://web.archive.org/web/20100706133017/https:/www.marshall.org/

pdf/materials/743.pdf.

47 See, for example, Xavier Vavasseur, “Japan Commissions New Maya-Class AEGIS Destroyer JS Haguro はぐろ

DDG-180,” Naval News, March 19, 2021; Yomiuri Shimbun, “Japan Commissions 8th Aegis Destroyer Haguro,” Japan

News, March 20, 2021.

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radar technology that would use Japanese semiconductors to more than double the detection

range of the Aegis missile defense system.”48

South Korea

An October 12, 2018, press report states that “the South Korean military has decided to buy shipbased SM-3 interceptors to thwart potential ballistic missile attacks from North Korea, a top

commander of the Joint Chiefs of Staff revealed Oct. 12.”49 As stated earlier, an October 16,

2023, press report states that South Korea’s newest Aegis destroyer will be BMD-capable.

Other Countries

Other countries that MDA views as potential naval BMD operators (using either the Aegis BMD

system or some other system of their own design) include the United Kingdom, the Netherlands,

Spain, Germany, Denmark, and Australia. Spain, South Korea, and Australia either operate, are

building, or are planning to build Aegis ships. The other countries operate destroyers and frigates

with different combat systems that may have potential for contributing to BMD operations.

Aeigs BMD Program Funding

The Aegis BMD program is funded mostly through MDA’s budget. The Navy’s budget provides

additional funding for Aegis BMD-related efforts. Table 1 shows requested MDA procurement

and research and development funding for Aegis BMD efforts under MDA’s FY2026 budget

submission.

Table 1. FY2026 MDA Procurement and

R&D Funding Line Items for Aegis BMD Efforts

(In millions of dollars, rounded to nearest tenth; totals may not add due to rounding)

FY26 Request

Procurement line items

Aegis BMD (line 46)

(SM-3 Block IB missile quantity)

SM-3 Block IIA (line 49)

(SM-3 Block IIA missile quantity)

Aegis Ashore Phase III (line 53)

Aegis BMD hardware and software (line 58)

SUBTOTAL Procurement line items above

Research and development (RDT&E) line items

Aegis BMD (PE 0603892C) (line 90)

Aegis BMD Test (PE 0604878C) (line 125)

Land-based SM-3 (PE 0604880C) (line 127)

SUBTOTAL RDT&E line items above

994.4

153.6

24.6

1,172.6

TOTAL Procurement and RDT&E line items above

1,634.6

0

(0)

444.8

(12)

0

17.2

462.0

48 Nikkei staff writers, “US Taps Japan Radar Tech to Double Missile Defense Range,” Nikkei Asian Review, July 6,

2018.

49 Jeff Jeong, “South Korea to Buy Ship-Based Interceptors to Counter Ballistic Missile Threats,” Defense News,

October 12, 2018.

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Source: Table prepared by CRS based on FY2026 MDA budget submission. Requested funding figures include

funding provided in FY2025 reconciliation act that DOD applied to its FY2026 budget submission.

Research and development funding in the table for the land-based SM-3 is funding for Aegis

Ashore sites. MDA’s budget also includes additional funding not shown in the table for operations

and maintenance (O&M) and military construction (MilCon) for the Aegis BMD program.

Issues for Congress

Annual Funding Request

One issue for Congress is whether to approve, reject, or modify MDA’s annual procurement and

research and development funding requests for the program. In considering this issue, Congress

may consider various factors, including whether the work that MDA is proposing to fund for the

fiscal year in question is properly scoped and scheduled, and accurately priced.

Program Deliveries, Testing, and Technical Risk

Another potential oversight issue for Congress concerns deliveries, testing, and technical risk in

the Aegis BMD program.

January 2025 DOT&E Report

A January 2025 report from DOD’s Director, Operational Test and Evaluation (DOT&E)—

DOT&E’s annual report for FY2024—states the following regarding the Aegis BMD system:

Aegis BMD has demonstrated the capability to intercept non-separating, simpleseparating, and complex-separating ballistic missiles in the midcourse phase of flight with

SM-3 guided missiles, although flight testing and M&S [modeling and simulation] have

not addressed all expected threat types, threat features, and raid sizes. In FY24, Aegis BMD

conducted its first-ever integrated air and missile defense engagement with a raid of

ballistic missiles and a concurrent raid of cruise missiles, and its most stressing engagement

against a ballistic missile target with countermeasures. In April 2024, for the first time in a

live combat environment, two Aegis BMD destroyers successfully engaged Iranian

ballistic missile threats targeting Israel with SM-3 Block IB guided missiles. In FY24 and

prior years, Aegis BMD has demonstrated a capability to intercept select ballistic missiles

in the terminal phase of flight with its Sea-Based Terminal capability with SM-6 guided

missiles.

All fielded Aegis BMD variants have demonstrated sufficient reliability, with operational

availabilities that exceed the specification. SM-3 Block IB Threat Upgrade and SM-3

Block IIA guided missiles are reliable, as they meet their threshold reliability metrics, but

not with statistical confidence because of the relatively small number of live firings to date.

The full production acquisition decision memorandums for the SM-3 Block IB and SM-3

Block IIA require periodic flight testing of these missiles throughout the life of the

program, which improves reliability data counts over time. SM-6 missiles have been

reliable in anti-air warfare and BMD flight testing.50

May 2023 GAO Report

A May 2023 GAO report on U.S. BMD systems, including the Aegis BMD system, stated the

following:

50 Director, Operational Test & Evaluation, FY 2024 Annual Report, January 2025, p. 379.

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DELIVERIES

MDA did not meet its fiscal year 2022 goal for SM-3 Block IB interceptors as five planned

interceptors were delivered after the fiscal year ended. MDA, however, delivered nine

backlogged interceptors that were previously delayed due to a flight test failure. The Aegis

program temporarily halted deliveries to investigate the failure, but missile production did

not stop and deliveries subsequently resumed.

MDA also did not meet its goal for SM-3 Block IIA interceptors. Three interceptors

planned for fiscal year 2022 were not delivered. MDA was able to deliver six backlogged

interceptors that we previously reported were delayed due to missile assembly issues. The

Aegis program addressed the issues, which allowed them to resume deliveries.

As reported by the agency, in August 2022, the Director, MDA approved an acquisition

strategy to align SM-3 Block IB and Block IIA production under one contract. This

production alignment is expected to maximize efficiencies in program management and

obsolescence monitoring, among other synergies. According to MDA officials, they have

not identified any disadvantages with this strategy. This acquisition strategy is currently

under review by the Under Secretary of Defense for Acquisition and Sustainment to

support a production decision for SM-3 Block IIA.

TESTING

Aegis BMD conducted four flight tests in fiscal year 2022, including a successful intercept

test event that demonstrated its interoperability with Japanese and Korean systems. The

last test—Flight Test Experiment Aegis Weapon System-01—gathered data while an SM3 Block IIA interceptor engaged a modified medium range ballistic missile target in a nonintercept test.

Aegis BMD conducted two planned ground tests. Ground Test Integrated (GTI)-09 Sprint

1 provided data to support decisions related to system capabilities affecting United States

European Command and United States Central Command. GTI-ISR 21 assessed the

system’s interoperability with Israeli missile defense systems. Aegis BMD also

participated in GTI-08a—a delayed test originally planned for fiscal year 2020—which

provided data to support system capabilities decisions for Aegis and other missile defense

system elements.

A planned Aegis BMD operational cyber test was delayed to fiscal year 2024 due to

MDA’s changes to its test plan that affected planned ground and cyber tests.

OTHER PROGRAM INFORMATION

Aegis Ashore

We reported in June 2022 that delivery of the Aegis Ashore system to Poland was originally

planned for fiscal year 2018, but that construction challenges delayed delivery.1 Total

projected costs increased by 12 percent, including additional costs for retaining engineering

and security services during the delays. The site remains under construction, but MDA

officials stated there are no known technical risks. In addition, the Aegis Ashore program

recently met key milestones. Specifically, Aegis Light Off occurred in June 2022, which

signifies the initial powering up of the weapon system to observe if all integrated systems

are operational. The program completed physical installation of the system and

demonstrated it in October 2022. MDA expects to declare the site safe and technically

capable in early 2023 and Navy acceptance is anticipated for later in the year.

Safe Service Life Extension

The Aegis program has been able to extend the safe service life of SM-3 Block IA and

Block IB interceptors to ensure the interceptors can be used with no additional safety risk.

Under this effort, the safe service life of Block IA interceptors increased from 12 to 18

years and Block IB interceptors increased from 8 to 12 years. The safe service life of Block

IIA interceptors is currently 12 years and MDA is assessing the possibility to increase this

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to 16, or possibly up to 20, years. MDA officials described the process to extend an

interceptor’s safe service life, which includes testing and analysis of aged missile

components to determine their suitability for extended service. The testing and analysis is

conducted by industry and government stakeholders and subject matter experts at various

locations and laboratories. MDA officials said safe service life extensions have helped

address the challenge of meeting the Navy’s interceptor inventory requirements, which

typically entail high volume procurements and consistent repair and recertification

throughput.

Software Development

MDA officials stated the Navy started implementing a multi-stage Development, Security,

and Operations strategy to deliver software upgrades to Aegis platforms. The Navy started

using a software factory—an automated process to develop software—in fiscal year 2021

and now plans to eliminate their legacy system for developing and delivering coded

software capability in fiscal year 2024.2 According to MDA officials, by fiscal year 2030

the Navy intends for this approach to be the sole means for developing and delivering coded

software capability to all Aegis platforms. MDA officials explained this strategy provides

the opportunity to significantly increase the speed of software deliveries to the fleet, as well

as reduce costs and cybersecurity risk by integrating security functions in the development

process. They stated, however, there is risk since it is a significant transition from current

development strategies. They said the transition would require extensive retraining and

hiring of government personnel to fully execute the strategy, as well as additional costs to

develop the new required tools, such as software, models, and infrastructure.51

Regarding the development of a capability for the SM-6 to intercept hypersonic missiles, the

GAO report stated,

MDA has two main efforts under development to defend against hypersonic weapons:

• Glide Phase Intercept (GPI) is a program that includes a missile being designed to be fired

from Aegis-equipped ships to intercept a hypersonic weapon in the middle (or “glide”)

phase of its flight path.

• Hypersonic and Ballistic Tracking Space Sensor (HBTSS) is an effort to develop spacebased sensors to track and support the intercept of a hypersonic weapon….

GPI is expected to work with existing and future systems to provide hypersonic defense.

After a missile launch, SDA’s wide field of view satellites, capable of viewing large

portions of the globe, detect the threat launch and send sensor measurement data to BOA,

which generates track data with accuracy sufficient to cue HBTSS. HBTSS then acquires

the deployed Hypersonic Glide Vehicle (HGV) and collects precision angle measurements.

These measurements are processed by HBTSS, BOA, and Command, Control, Battle

Management, and Communications (C2BMC) to provide fire control quality tracks on the

HGV to Aegis for support of an engagement using GPI….

GPI STATUS AND CHALLENGES

Events and Milestones

By the early 2030s, the GPI program plans to deliver a prototype capability for testing,

demonstration data to inform further development, and 10 interceptors to be used for

testing. The program established a plan to acquire the capability and identified key events

and milestones for tracking development. The plan includes competitive development of

the GPI missile leveraging multiple contractors to begin the effort, but only one contractor

is anticipated to be selected to complete delivery of the prototype capability. In fiscal year

2022, MDA reported that three contractors were awarded Other Transaction Agreements

51 Government Accountability Office, Missile Defense[:] Annual Goals Unmet for Deliveries and Testing, GAO-23-

106011, May 2023, pp. 22-23.

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to initiate work on the GPI program.1 Later, in the fiscal year the program reported

selecting two contractors to continue the development of GPI into the next phase of the

acquisition process, technology development. In fiscal year 2023, the program expects to

focus efforts on technology maturity and applying top level requirements to component

level designs in preparation for the Preliminary Design Review….

The Preliminary Design Review is currently planned by the end of fiscal year 2027. The

GPI program also anticipates down-selecting from two to one contractor near this date to

continue until completing delivery of the prototype capability….

Challenges

Previously we found in June 2022 that MDA had not planned to conduct an Independent

Cost Estimate (ICE) or Independent Technical Risk Assessment (ITRA) for the GPI

program before the product development phase, which is after the technology development

phase. These assessments are required for certain elements by DOD Directive-Type

Memorandum 20-002 to mitigate risk. Since our reporting, MDA officials stated the Office

of Cost Assessment and Program Evaluation (CAPE) completed a preliminary ICE for the

GPI program in the August 2022 timeframe. As of February 2023, CAPE is working to

finalize the ICE pending the final President’s Budget program schedule. MDA officials

also stated the Office of the Under Secretary of Defense for Research and Engineering

completed an ITRA for the GPI program in the August 2022 timeframe as well. According

to MDA, the ITRA found that the program should address technical risks earlier in the

development schedule by building and testing hardware. The ITRA also recommended

earlier testing. We plan to review the ICE and ITRA to assess whether MDA has acquired

knowledge to manage risk for the GPI program.52

Inventories of BMD-Capable Interceptor Missiles

Another potential issue for Congress concerns the impact of Navy air and missile defense

operations in the Middle East in 2023-2025 on Navy inventories of BMD-capable interceptors

(SM-3 and SM-6 missiles) available for other potential contingencies, particularly a large-scale

conflict with China. Some observers have expressed concern about this issue, particularly given

annual production capacities for building these missiles and the resulting time that will be needed

to rebuild inventories. As discussed in a separate CRS report on Navy ship-based lasers,53

operations by U.S. Navy ships in the Red Sea and the Gulf of Aden in 2023-2025 to defend

commercial cargo ships (and themselves) from attacks by Houthi forces in Yemen using drones,

cruise missiles, and ballistic missiles54 have involved the reported use of scores of U.S. Navy

interceptor missiles, including BMD-capable interceptors.55 U.S. Navy operations in 2024 and

2025 in the Eastern Mediterranean to assist in defending Israel against Iranian ballistic missiles

have reportedly involved the use additional BMD-capable interceptors.56

52 Government Accountability Office, Missile Defense[:] Annual Goals Unmet for Deliveries and Testing, GAO-23-

106011, May 2023, pp. 34-35.

53 See CRS Report R44175, Navy Shipboard Lasers: Background and Issues for Congress, by Ronald O'Rourke.

54 For general background on these attacks, see CRS Insight IN12301, Houthi Attacks in the Red Sea: Issues for

Congress, by Jeremy M. Sharp.

55 See for example, Sam LaGrone, “SM-3 Ballistic Missile Interceptor Used for First Time in Combat, Officials

Confirm,” USNI News, April 15 2024; Caitlyn Burchett, “2 Navy Destroyers Help Defend Israel, Intercept Ballistic

Missiles Launched by Iran,” Stars and Stripes, October 1, 2024.

56 See, for example, C. Todd Lopez, “U.S. Assets in Mediterranean Again Helped Defend Israel Against Iranian

Missiles,” DOD News, October 1, 2025; Noah Robertson, “Navy Warships Helped Take Down Iran’s Attack on Israel,

Pentagon Says,” Defense News, October 1, 2025; Howard Altman, “U.S. Navy Destroyers ‘Successfully Engaged’

Iranian Ballistic Missiles On Their Way To Israel,” The War Zone, October 2, 2024; Jacob Magid, “US: We Will Help

(continued...)

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An October 11, 2024, press report stated: “Navy leadership has said that it needs many more SM3s to counter threats in the Pacific, like China, but it’s burning through these weapons in conflicts

in the Middle East without sufficient plans to replace them.”57 A June 24, 2025, press report

stated:

US Navy warships are burning through one of the top ballistic missile interceptors at an

“alarming rate,” the admiral overseeing naval operations told lawmakers on Tuesday [June

24].

During a Senate Appropriations Committee hearing, Sen. Brian Schatz of Hawaii said US

forces had expended large amounts of munitions to defend Israel from Iranian strikes

during the latest round of conflict in the Middle East and asked whether the Navy had all

the Standard Missile-3 interceptors that it needed to be ready for other global threats.

Adm. James Kilby, the acting chief of naval operations, said that the service did have a

sufficient supply of interceptors but that “we are, to your point, using them at an alarming

rate.” 58

A December 2025 report from the Center for Strategic and International Studies (CSIS) examined

estimated inventories and production rates for BMD-capable interceptors, including Navy SM-3

and SM-6 interceptors and Army Terminal High Altitude Area Defense (THAAD) and Patriot

Advanced Capability-3 (PAC-3) Missile Segment Enhanced (MSE) interceptors. The report

states:

As missiles have become weapons of choice, missile defenses have become the table stakes

of modern conflict. The recent THAAD, MSE, and SM-3 employment in the Middle East

shows that current inventories and production rates of missile defense interceptors are

insufficient. Their employment in unexpected conflicts should be planned for, rather than

come as a surprise that disrupts the inventory and prompts considerable course corrections.

If every use of a U.S. air and missile defense interceptor is going to produce another round

of discourse about inventories, then it is time to reevaluate either the deployments

themselves or how to procure enough interceptors to avoid handwringing.59

Potential Contribution from Lasers

Another potential issue for Congress concerns the potential for ship-based lasers to contribute in

coming years to Navy terminal-phase BMD operations and the impact this might eventually have

on required numbers of ship-based BMD interceptor missiles. A separate CRS report discusses

the potential value of ship-based lasers for performing various missions, including, potentially,

terminal-phase BMD operations.60

Israel Exact ‘Severe Consequences’ from Iran for Missile Attack,” Times of Israel, October 2, 2024; Geoff

Ziezulewicz, “Watch the USS Bulkeley Help Shoot Down Iran’s Missile Attack on Israel,” Navy Times, October 3,

2024; Tara Copp and Lolita C. Baldor, “US Helps Israel Shoot Down Barrage of Iranian Missiles,” Associated Press,

June 13 2025; Nicholas Slayton, “Navy Destroyer, Air Defense Systems Help Intercept Iranian Missiles,” Task &

Purpose, June 15, 2025; Jake Epstein, “US Navy Warships Picked Up Multiple New Iranian Ballistic Missile Kills in

the Latest Defense Of Israel,” Business Insider, June 30, 2025; U.S. Naval Forces Europe Public Affairs, “Senior

Military Leaders Praise Destroyer Sailors during Souda Bay Visit,” U.S. Navy press release dated June 30, 2025.

57 Jake Epstein and Chris Panella, “The US Navy is Burning through Missiles in the Middle East That It Would Need in

a War with China,” Business Insider, October 11, 2024.

58 Jake Epstein, “US Navy Warships Are Firing Top Ballistic Missile Interceptors at an ‘Alarming Rate,’ Admiral

Says,” Business Insider, June 24, 2025. See also Shelby Holliday, Anat Peled, and Drew FitzGerald, “Israel’s 12-Day

War Revealed Alarming Gap in America’s Missile Stockpile,” Wall Street Journal, June 24, 2025.

59 Wes Rumbaugh, The Depleting Missile Defense Interceptor Inventory, Center for Strategic and International Studies

(CSIS), December 2025, p. 8.

60 See CRS Report R44175, Navy Shipboard Lasers: Background and Issues for Congress, by Ronald O'Rourke.

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Issues in Earlier Years

Below are short discussions of issues for Congress relating to the Aegis BMD program from

earlier years.

Estimating and Reporting Costs

One earlier issue for Congress concerned the adequacy of MDA’s cost estimating and its reporting

of costs. A February 2022 GAO report on MDA’s cost estimating and reporting of costs for

missile defense programs, including the Aegis BMD program, stated,

The Department of Defense’s (DOD) Missile Defense Agency (MDA) is continuing efforts

to deliver systems to the warfighter that will protect against enemy missiles. However,

shortfalls persist with MDA’s program and flight test cost estimates and reporting.

Program cost estimates. MDA continues to omit the military services’ operations and

sustainment costs from the program life-cycle cost estimates.... By omitting these costs,

MDA limits decision-makers’ insight into the full financial commitments needed for

affordability and funding determinations....

Flight test cost estimates. Accuracy issues linger with MDA’s flight test cost estimates that

could skew the agency’s annual $1.3 billion [flight test] funding request, such as not being

regularly updated with actual costs. However, MDA is taking steps to improve these cost

estimates by using a new cost model, among other things....

Program cost reporting. MDA continues to adjust program baselines without clear

traceability over time. MDA also forgoes recurrent comparisons to the original baseline.

Such adjustments and omissions impede decision-makers’ awareness of each program’s

cost performance and total system cost....

Flight test cost reporting. Congress required MDA to report on flight test costs, but we

found the information lacking due to the agency’s reporting methodology. MDA only

accounted for about $1.3 billion of at least $3.5 billion in funding the agency requested for

flight testing between March 2017 and September 2020. Moreover, the reporting

requirement ended in December 2021. Without further reporting on complete flight test

costs, Congress does not have information needed to facilitate holding the agency

accountable for its spending.61

Potential for Intercepting ICBMs

Another earlier issue for Congress concerned what role the Aegis BMD program should play in

defending the U.S. homeland against attack from ICBMs. With the advent of the SM-3 Block IIA

interceptor, DOD evaluated the potential for the Aegis BMD system to intercept certain ICBMs.

Section 1680 of the FY2018 National Defense Authorization Act (H.R. 2810/P.L. 115-91 of

December 12, 2017) directed DOD to “conduct a test to evaluate and demonstrate, if

technologically feasible, the capability to defeat a simple intercontinental ballistic missile threat

using the standard missile 3 block IIA missile interceptor.” DOD’s January 2019 missile defense

review report stated the following:

The SM-3 Blk IIA interceptor is intended as part of the regional missile defense

architecture, but also has the potential to provide an important “underlay” to existing GBIs

[ground-based interceptors] for added protection against ICBM threats to the homeland.

This interceptor has the potential to offer an additional defensive capability to ease the

61 Government Accountability Office, Missile Defense[:] Addressing Cost Estimating and Reporting Shortfalls Could

Improve Insight into Full Costs of Programs and Flight Tests, GAO-22-104344, February 2022, highlights page (PDF

page 2 of 58).

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burden on the GBI system and provide continuing protection for the U.S. homeland against

evolving rogue states’ long-range missile capabilities.

Congress has directed DoD to examine the feasibility of the SM-3 Blk IIA against an

ICBM-class target. MDA will test this SM-3 Blk IIA capability in 2020. Due to the

mobility of sea-based assets, this new underlay capability will be surged in a crisis or

conflict to further thicken defensive capabilities for the U.S. homeland. Land-based sites

in the United States with this SM-3 Blk IIA missile could also be pursued.62

On November 16, 2020, MDA announced that the congressionally directed ICBM-intercept flight

test, called FTM-44, had been conducted on that date and had resulted in a successful intercept of

the ICBM-representative target. MDA stated that “FTM-44, originally scheduled for May 2020,

was delayed due to restrictions in personnel and equipment movement intended to reduce the

spread of COVID-19. FTM-44 satisfies a Congressional mandate to evaluate the feasibility of the

SM-3 Block IIA missile’s capability to defeat an ICBM threat before the end of 2020.”63 A

November 17, 2020, press report about the flight test stated that “the unarmed ICBM was a

replica of a target flown against the Ground-based Midcourse Defense system during a March

2019 flight test that featured a salvo launch of a pair of interceptors.”64 An April 2021 GAO

report on deliveries and testing of U.S. missile defense systems in FY2020 stated the following:

MDA’s effort to include the SM-3 Block IIA interceptor in a new “layered” homeland

defense against intercontinental ballistic missile (ICBM) threats targeting the U.S. could

introduce considerable cost, schedule, and performance uncertainty to a program that has

just entered initial production. The GMD weapon system currently provides defense

against ICBMs, but this new effort would add the SM-3 Block IIA and THAAD weapon

system as layers underneath that provided by GMD. For further details on the GMD and

THAAD weapon systems see their respective appendixes.

ICBM intercepts are more challenging than the IRBM intercepts for which the SM-3 IIA

was originally designed. MDA’s most recent attempt to create a system for intercepting

ICBMs, known as the Redesigned Kill Vehicle (RKV), re-used some parts from the SM-3

Block IIA. DOD cancelled the RKV before it could complete development after significant

cost and schedule overruns and questions about the ability of the design to overcome

specific performance risks. Parts re-used from the SM-3 Block IIA were implicated in some

of the RKV’s performance shortfalls. Even so, planning for an anti-ICBM capability for

the SM-3 Block IIA continued during and even after the RKV’s termination.

Achieving such a capability will require surmounting several challenges. According to

MDA, during the November 2020 flight test named FTM-44, the SM-3 Block IIA struck a

simple ICBM target. This was not an operational test, however, and it was executed under

highly favorable conditions. More development work is needed for the SM-3 Block IIA to

support a layered homeland defense capability. MDA documents show that the agency now

plans to develop and procure an upgraded version of the SM-3 Block IIA for the specific

purpose of fulfilling the homeland defense mission.65

62 Department of Defense, Missile Defense Review 2019, released January 17, 2019, p. 55. David Axe, “The U.S.

Navy’s New Missile Defense Is a Bad Idea,” National Interest, January 17, 2019.

63 Missile Defense Agency News release 20NEWS-0003, “U.S. Successfully Conducts SM-3 Block IIA Intercept Test

Against an Intercontinental Ballistic Missile Target,” November 16, 2020.

64 Jason Sherman, “SM-3 Block IIA Intercepts ICBM Target, Validating Potential for Homeland Defense

‘Underlayer,’” Inside Defense, November 17, 2020.

65 Government Accountability Office, Missile Defense[:] Fiscal Year 2020 Delivery and Testing Progressed, but

Annual Goals Unmet, GAO-21-314, April 2021, p. 24. See also Jen Judson, “Watchdog Expresses Concern over Using

US Navy Interceptor for Homeland Missile Defense,” Defense News, April 29, 2021.

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A May 13, 2021, press report stated

The Missile Defense Agency proved that a Navy destroyer with a Standard Missile-3 Block

IIA can stop a simple intercontinental ballistic missile threat, but more work remains to

prove whether this combination could contribute to homeland defense, the MDA director

said Wednesday [May 12].

Vice Adm. Jon Hill described the Flight Test Aegis Weapon System (FTM) 44, which took

place in the Pacific in November after pandemic-related delays earlier in the year: A simple

ICBM target was launched from the Army’s Ronald Reagan Ballistic Missile Defense Test

Site on the Kwajalein Atoll in the Marshall Islands. Satellites detected the launch, and a

slew of satellites and sensors, including on the Pacific Missile Range Facility in Hawaii,

tracked the target. Arleigh Burke-class destroyer USS John Finn (DDG-113), positioned

hundreds of miles east of Hawaii, launched an SM-3 Block IIA missile from its deck based

on its best fire control solution at the time, and the missile itself maneuvered to successfully

hit the target as it received more information in flight.

The goal of the test, Hill said while speaking at the annual McAleese FY 2022 Defense

Programs Conference, was “to prove that we have the ability to leverage the robustness in

the [Aegis] program, so that was really the first test just to see if it’s feasible. And we

learned a lot.”

Hill said the crew of John Finn, with limited data due to limited sensor coverage across the

vast Pacific, maneuvered the ship to get the highest probability of kill.

“It maneuvered, shot the missile; lots of uncertainty because of lack of sensor coverage for

such a long-range flight where we were doing the exercise. So what we actually saw was a

really high divert [from the missile]. So kind of two walkaways from that first test, which

is why I think it was really important, was that it was the longest propagated error or

uncertainty that we’ve ever seen in any test. And then we had the highest divert—that

meant the [SM-3 IIA] missile was maneuvering to actually take it out, and it still took it

out, which is really great,” Hill continued.

“In terms of feasibility, did we accomplish the mission? Absolutely. Every test objective

achieved in November.”

Hill was asked about an April Government Accountability Office report that cited concerns

about the Aegis Combat System/SM-3 IIA pairing for the homeland defense mission—as

opposed to the regional defense mission it was built for, to protect a high-value asset such

as an aircraft carrier from an intermediate-range missile—and whether the simple ICBM

target used in the November test was representative of the real world.

“So what’s next? What’s next is to go against a more complex intercontinental ballistic

missile threat, and maybe even change the scenario. This scenario was a defense of Hawaii

scenario against a rogue nation—you guess which one out there in the Pacific—and in the

future we’re going to go to a more complex [threat], and that’s within the next couple

years,” he said.

“So we’re still analyzing data from November, and then we’re going to make upgrades and

changes to the combat system, and we’ll make changes to the missile in terms of threat set

to take on a higher end class threat.”

MDA and the military services would have to further integrate systems together to make

this a credible layer in the homeland defense network, Hill said. During the November test,

the MDA commanded and controlled the event from the Missile Defense Interoperability

and Operations Center in Colorado Springs, Colo., using the Command and Control Battle

Management and Communication System (C2BMC) to receive satellite and sensor data

and feed it to John Finn, which fired its missile on remote without having access to the

sensor data itself. While that worked in a controlled environment, for a permanent

homeland defense mission the ship would need to be better integrated into U.S. Northern

Command’s network to fully share information and targeting data.

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Hill said that Aegis has been integrated to operate with the Terminal High Altitude Area

Defense system, and THAAD has been integrated with the Patriot missile defense system,

but MDA hasn’t integrated all the regional defense systems with homeland defense

systems.

Beyond the actual integration and engineering work, Hill added that there was a policy

question to answer, too.

“Do we want ships in that role of being off the West Coast … defending against ICBMs as

a layer to the Ground-Based Mid-Course Defense? That’s an incredible conversation,

we’re having that now, and it’s hard to predict where it will go.”

Asked on Thursday during the Naval Postgraduate School’s acquisition research

symposium if the Navy has the capacity and appetite to use destroyers for homeland

defense, Hill said much of it comes down to what ships are available for the mission.

“I think if you asked Gen. [Glen] VanHerck from NORTHCOM about his confidence in

defending the nation today, the answer would be confident. But as the threat evolves, right,

you start to see a little change in that view. And so it’s been viewed for a while that the

Navy can play a role in that area, but it becomes an asset problem,” Hill said. “There are

only so many ships we have up there. And they’re multi-mission ships, and they have a lot

of roles around the globe to execute.”66

A June 22, 2021, press report stated

The Pentagon’s No. 2 official has ordered 11 missile interceptors transferred from research

and development for possible deployment on Navy ships in the Pacific or European regions

after a test in November indicated they could stop an intercontinental ballistic missile.

In the test, the USS John Finn intercepted a mock ICBM intended to simulate one that

could be launched at Hawaii by North Korea. The destroyer, operating near Hawaii, fired

off one of the Standard Missile-3 model Block IIA interceptors built by Raytheon

Technologies Corp. at the target launched from Kwajalein Atoll in the Marshall Islands.

Deputy Defense Secretary Kathleen Hicks informed Congress May 27 of her rationale for

transferring the interceptors, although she didn’t disclose it publicly.

“The missiles have conducted successful intercept tests and their deployment is in the

important interest of our national security,” Hicks spokesman Jamal Brown said in an email

this month. The transfer to the Navy marks the first major missile defense initiative of the

Biden administration.

Although the Navy’s Aegis combat system, which launched the missile, and the interceptor

“were not designed to defeat an ICBM-class target, this test demonstrated some potential

limited capability,” Vice Admiral Jon Hill, director of the Missile Defense Agency, said in

testimony to Congress last week.67

Required vs. Available Numbers of BMD-Capable Aegis Ships

Another earlier issue for Congress concerned required versus available numbers of BMD-capable

Aegis ships. Some observers have expressed concern about the potential operational implications

of a shortfall in the available number of BMD-capable Aegis ships relative to the required

66 Megan Eckstein, “MDA: Test of DDG, Standard Missile-3 IIA a Good Start, But More Work Needed on Homeland

Defense Mission,” USNI News, May 13, 2021. See also Jason Sherman, “MDA Planning Second SM-3 Block IIA

Flight Test Against ICBM Target; New Development and Upgraded Interceptor Needed,” Inside Defense, May 12,

2021; Rich Abott, “MDA Planning Second Test of SM-3 IIA Against ICBM Target,” Defense Daily, May 17, 2021.

67 Anthony Capaccio, “U.S. Navy Ships Close to Getting Interceptors That Could Stop an ICBM,” Bloomberg, June 22,

2021.

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number. Regarding the required number of BMD-capable Aegis ships, an August 15, 2018, Navy

information paper stated the following:

The [Navy’s] 2016 Force Structure Assessment [FSA]68 sets the requirement [for BMDcapable ships] at 54 BMD-capable ships, as part of the 104 large surface combatant

requirement, to meet Navy unique requirements to support defense of the sea base and

limited expeditionary land base sites….

The minimum requirement for 54 BMD ships is based on the Navy unique requirement as

follows. It accepts risk in the sourcing of combatant commander (CCDR) requests for

defense of land.

- 30 to meet CVN escort demand for rotational deployment of the carrier strike groups

- 11 INCONUS for independent BMD deployment demand

- 9 in forward deployed naval forces (FDNF) Japan to meet operational timelines in

USINDOPACOM

- 4 in FDNF Europe for rotational deployment in EUCOM.69

Burden of BMD Mission on U.S. Navy Aegis Ships

A related earlier issue for Congress concerned the burden that BMD operations may be placing on

the Navy’s fleet of Aegis ships, particularly since performing BMD patrols requires those ships to

operate in geographic locations that may be unsuitable for performing other U.S. Navy missions,

and whether there are alternative ways to perform BMD missions now performed by U.S. Navy

Aegis ships, such as establishing more Aegis Ashore sites. A June 16, 2018, press report stated the

following:

The U.S. Navy’s top officer wants to end standing ballistic missile defense patrols and

transfer the mission to shore-based assets.

Chief of Naval Operations Adm. John Richardson said in no uncertain terms on June 12

that he wants the Navy off the tether of ballistic missile defense patrols, a mission that has

put a growing strain on the Navy’s hard-worn surface combatants, and the duty shifted

towards more shore-based infrastructure.

“Right now, as we speak, I have six multi-mission, very sophisticated, dynamic cruisers

and destroyers―six of them are on ballistic missile defense duty at sea,” Richardson said

during his address at the U.S. Naval War College’s Current Strategy Forum. “And if you

know a little bit about this business you know that geometry is a tyrant.

“You have to be in a tiny little box to have a chance at intercepting that incoming missile.

So, we have six ships that could go anywhere in the world, at flank speed, in a tiny little

box, defending land.”

Richardson continued, saying the Navy could be used in emergencies but that in the long

term the problem demands a different solution.

“It’s a pretty good capability and if there is an emergent need to provide ballistic missile

defense, we’re there,” he said. “But 10 years down the road, it’s time to build something

on land to defend the land. Whether that’s AEGIS ashore or whatever, I want to get out of

the long-term missile defense business and move to dynamic missile defense.”

68 The FSA is the Navy’s analysis, performed every few years, that establishes the Navy’s ship force structure

requirements. For further discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:

Background and Issues for Congress, by Ronald O'Rourke.

69 Navy information paper dated August 15, 2018, entitled “Ballistic Missile Defense (BMD) Capable Ships

requirement,” provided by Navy Office of Legislative Affairs to CBO and CRS on August 15, 2018. The information

paper was requested by CBO.

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The unusually direct comments from the CNO come amid growing frustration among the

surface warfare community that the mission, which requires ships to stay in a steaming box

doing figure-eights for weeks on end, is eating up assets and operational availability that

could be better used confronting growing high-end threats from China and Russia.

The BMD mission was also a factor in degraded readiness in the surface fleet. Amid the

nuclear threat from North Korea, the BMD mission began eating more and more of the

readiness generated in the Japan-based U.S. 7th Fleet, which created a pressurized situation

that caused leaders in the Pacific to cut corners and sacrifice training time for their crews,

an environment described in the Navy’s comprehensive review into the two collisions that

claimed the lives of 17 sailors in the disastrous summer of 2017.

Richardson said that as potential enemies double down on anti-access technologies

designed to keep the U.S. Navy at bay, the Navy needed to focus on missile defense for its

own assets.

“We’re going to need missile defense at sea as we kind of fight our way now into the battle

spaces we need to get into,” he said. “And so restoring dynamic maneuver has something

to do with missile defense.70

A June 23, 2018, press report stated the following:

The threats from a resurgent Russia and rising China―which is cranking out ships like it’s

preparing for war―have put enormous pressure on the now-aging [U.S. Navy Aegis

destroyer] fleet. Standing requirements for BMD patrols have put increasing strain on the

U.S. Navy’s surface ships.

The Navy now stands at a crossroads. BMD, while a burden, has also been a cash cow that

has pushed the capabilities of the fleet exponentially forward over the past decade. The

game-changing SPY-6 air and missile defense radar destined for DDG Flight III, for

example, is a direct response to the need for more advanced BMD shooters. But a smaller

fleet, needed for everything from anti-submarine patrols to freedom-of-navigation missions

in the South China Sea, routinely has a large chunk tethered to BMD missions.

“Right now, as we speak, I have six multimission, very sophisticated, dynamic cruisers and

destroyers―six of them are on ballistic missile defense duty at sea,” Chief of Naval

Operations Adm. John Richardson said during an address at the recent U.S. Naval War

College’s Current Strategy Forum. “You have to be in a tiny little box to have a chance at

intercepting that incoming missile. So we have six ships that could go anywhere in the

world, at flank speed, in a tiny little box, defending land.”

And for every six ships the Navy has deployed in a standing mission, it means 18 ships are

in various stages of the deployment cycle preparing to relieve them.

The Pentagon, led by Defense Secretary Jim Mattis, wants the Navy to be more flexible

and less predictable―“dynamic” is the buzzword of moment in Navy circles. What

Richardson is proposing is moving standing requirements for BMD patrols away from

ships underway and all the associated costs that incurs, and toward fixed, shore-based sites,

and also surging the Navy’s at-sea BMD capabilities when there is an active threat....

In a follow-up response to questions posed on the CNO’s comments, Navy spokesman

Cmdr. William Speaks said the Navy’s position is that BMD is an integral part of the

service’s mission, but where long-term threats exist, the Navy should “consider a more

persistent, land-based solution as an option.”

“This idea is not about the nation’s or the Navy’s commitment to BMD for the U.S. and

our allies and partners―the Navy’s commitment to ballistic missile defense is rock-solid,”

70 David B. Larter, “The US Navy Is Fed Up with Ballistic Missile Defense Patrols,” Defense News, June 16, 2018. See

also Paul McLeary, “Will Budget Crunch Pentagon Laser & Space Investments?” Breaking Defense, November 13,

2018.

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Speaks said. “In fact, the Navy will grow the number of BMD-capable ships from 38 to 60

by 2023, in response to the growing demand for this capability.

“The idea is about how to best meet that commitment. In alignment with our national

strategic documents, we have shifted our focus in an era of great power competition―this

calls us to think innovatively about how best to meet the demands of this mission and

optimize the power of the joint force.”...

While the idea of saving money by having fixed BMD sites and freeing up multimission

ships is sensible, it may have unintended consequences, said Bryan McGrath, a retired

destroyer skipper and owner of the defense consultancy The FerryBridge Group.

“The BMD mission is part of what creates the force structure requirement for large surface

combatants,” McGrath said on Twitter after Defense News reported the CNO’s comments.

“Absent it, the number of CG’s and DDG’s would necessarily decline. This may in fact be

desirable, depending on the emerging fleet architecture and the roles and missions debate

underway. Perhaps we need more smaller, multi-mission ships than larger, more expensive

ones.

“But it cannot be forgotten that while the mission is somewhat wasteful of a capable, multimission ship, the fact that we have built the ships that (among other things) do this mission

is an incredibly good thing. If there is a penalty to be paid in peacetime sub-optimization

in order to have wartime capacity—should this not be considered a positive thing?”

McGrath went on to say that the suite of combat systems that have been built into Aegis

have been in response to the BMD threat. And indeed, the crown jewels of the surface

fleet―Aegis Baseline 9 software, which allows a ship to do both air defense and BMD

simultaneously; the Aegis common-source library; the forthcoming SPY-6; cooperative

engagement―have come about either in part or entirely driven by the BMD mission....

A Navy official who spoke on condition of anonymity, to discuss the Navy’s shifting

language on BMD, acknowledged the tone had shifted since the 2000s when the Navy

latched onto the mission. But the official added that the situation more than a decade later

has dramatically shifted.

“The strategic environment has changed significantly since the early 2000s―particularly

in the western Pacific. We have never before faced multiple peer rivals in a world as

interconnected and interdependent as we do today,” the official said. “Nor have we ever

seen technologies that could alter the character of war as dramatically as those we see

emerging around us. China and Russia have observed our way of war and are on the move

to reshape the environment to their favor.”

In response to the threat and Defense Secretary Jim Mattis’ desire to use the force more

dynamically, the Navy is looking at its options, the official said. “This includes taking a

look at how we employ BMD ships through the lens of great power competition to compete,

deter and win against those who threaten us.”71

A January 29, 2019, press report stated the following:

The Navy is looking to get out of the missile defense business, the service’s top admiral

said today, and the Pentagon’s new missile defense review might give the service the offramp it has been looking for to stop sailing in circles waiting for ground-based missile

launches.

This wasn’t the first time Adm. John Richardson bristled in public over his ships sailing in

“small boxes” at sea tasked with protecting land, when they could be out performing other

71 David B. Larter, “As Threats Mount, US Navy Grapples with Costly Ballistic Missile Defense Mission,” Defense

News, June 23, 2018.

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missions challenging Chinese and Russian adventurism in the South China Sea and the

North Atlantic….

“We’ve got exquisite capability, but we’ve had ships protecting some pretty static assets

on land for a decade,” Richardson said at the Brookings Institute. “If that [stationary] asset

is going to be a long-term protected asset, then let’s build something on land and protect

that and liberate these ships from this mission.”

Japan is already moving down the path of building up a more robust ground-based sensor

and shooter layer, while also getting its own ships out to sea armed with the Aegis radar

and missile defense system, both of which would free up American hulls from what

Richardson on Monday called “the small [geographic] boxes where they have to stay for

ballistic missile defense.”72

Allied Burden Sharing: U.S. vs. Allied Contributions to Regional BMD

Capabilities

Another earlier issue for Congress concerned allied burden sharing—how allied contributions to

regional BMD capabilities and operations compare to U.S. naval contributions to overseas

regional BMD capabilities and operations, particularly in light of constraints on U.S. defense

spending, worldwide operational demands for U.S. Navy Aegis ships, and calls by some U.S.

observers for increased allied defense efforts. The issue can arise in connection with both U.S.

allies in Europe and U.S. allies in Asia. Regarding U.S. allies in Asia, a December 12, 2018, press

report stated the following:

In June, US Navy Chief of Naval Operations (CNO) Admiral John Richardson said during

a speech at the US Naval War College that the US Navy should terminate its current

practice of dedicating several US Navy warships solely for Ballistic Missile Defense

(BMD).

Richardson wanted US warships to halt BMD patrols off Japan and Europe as they are

limiting, restrictive missions that could be better accomplished by existing land-based

BMD systems such as Patriot anti-missile batteries, the US Terminal High Altitude Area

Defense (THAAD) anti-missile system and the Aegis Ashore anti-missile system.

In the months since dropping his bombshell, Richardson—and much of the debate—has

gone quiet.

“My guess is the CNO got snapped back by the Pentagon for exceeding where the debate

actually stood,” one expert on US naval affairs told Asia Times.

But others agree with him. Air Force Lt Gen Samuel A Greaves, the director of the US

Missile Defense Agency (MDA), acknowledges Richardson’s attempts to highlight how

these BMD patrols were placing unwelcome “strain on the (US Navy’s) crews and

equipment.”

But there are complications. While it may free US Navy warships for sea-control, rather

than land defense, there is a concern that next- generation hypersonic cruise missiles could

defeat land-based BMD systems, such as Aegis Ashore, while the US Navy’s Aegisequipped warships offer the advantages of high-speed mobility and stealth, resulting in

greater survivability overall.

As Japan prepares to acquire its first Aegis Ashore BMD system – and perhaps other

systems such as the THAAD system which has been deployed previously in Romania and

72 Paul McLeary, “The Navy Has Had Enough of Missile Defense And Sees Its Chance,” Breaking Defense, January

28, 2019.

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South Korea – the possibility that the US Navy will end its important BMD role represents

abrupt change….

Japan’s decision to deploy Aegis Ashore can fill in any gap created by a possible US Navy

cessation of BMD patrols. “The land-based option is more reliable, less logistically

draining, and despite being horrendously expensive, could be effective in the sense that it

provides a degree of reassurance to the Japanese people and US government, and

introduces an element of doubt of missile efficacy into [North Korean] calculations,” said

[Garren Mulloy, Associate Professor of International Relations at Daito Bunka University

in Saitama, Japan], adding, however, that these systems could not cover Okinawa.

“Fixed sites in Japan could be vulnerable, and the Aegis vessels provide a flexible forwarddefense, before anything enters Japanese airspace, but with obviously limited reactions

times,” Mulloy said. “Aegis Ashore gives more reaction time – but over Japanese

airspace.”…

The silence about this sudden possible shift in the US defense posture in the western Pacific

is understandable: it is a sensitive topic in Washington and Tokyo. However, the Trump

administration has urged its allies to pay more for their own defense needs and to support

US troops deployed overseas.

Meanwhile, Tokyo needs to proceed cautiously given the likelihood that neighbors might

view a move on BMD as evidence that Tokyo is adopting an increasingly aggressive

defense posture in the region.

But for them, it is a no-win situation. If the US does ditch the BMD patrol mission, China

and North Korea might view the shift as equally menacing given that it greatly enhances

the US Navy’s maritime warfare capabilities.73

Conversion of Hawaii Aegis Test Site

Another earlier issue for Congress was whether to convert the Aegis test facility in Hawaii into an

operational land-based Aegis BMD site. DOD’s January 2019 missile defense review report

stated, in a section on improving or adapting existing BMD systems, that

Another repurposing option is to operationalize, either temporarily or permanently, the

Aegis Ashore Missile Defense Test Center in Kauai, Hawaii, to strengthen the defense of

Hawaii against North Korean missile capabilities. DoD will study this possibility to further

evaluate it as a viable near-term option to enhance the defense of Hawaii. The United States

will augment the defense of Hawaii in order to stay ahead of any possible North Korean

missile threat. MDA and the Navy will evaluate the viability of this option and develop an

Emergency Activation Plan that would enable the Secretary of Defense to operationalize

the Aegis Ashore test site in Kauai within 30 days of the Secretary’s decision to do so, the

steps that would need to be taken, associated costs, and personnel requirements. This plan

will be delivered to USDA&S, USDR&E, and USDP within six months of the release of

the MDR.74

A January 25, 2019, press report stated the following:

The Defense Department will examine the funding breakdown between the Navy and the

Missile Defense Agency should the government make Hawaii’s Aegis Ashore Missile

Defense Test Center into an operational resource, according to the agency’s director.

“Today, it involves both Navy resources for the operational crews—that man that site—as

well as funds that come to MDA for research, development and test production and

sustainment,” Lt. Gen. Sam Greaves said of the test center when asked how the funding

73 Peter J. Brown, “Japan, US Silent over Ending Ballistic Missile Patrols,” Asia Times, December 12, 2018.

74 Department of Defense, Missile Defense Review 2019, released January 17, 2019, pp. 55-56.

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would shake out between the Navy and MDA should the Pentagon move forward with the

recommendation.75

75 Mallory Shelbourne, “DOD to Determine Funding Breakdown for Aegis Ashore Repurposing,” Inside the Navy,

January 25, 2019.

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Appendix. Reported Aegis BMD Flight Tests

Table A-1 presents a summary of reported Aegis BMD flight tests from 2002 to early 2024. The

table does not include

•

•

an operation on February 20, 2008, in which a BMD-capable Aegis cruiser

operating northwest of Hawaii used a modified version of the Aegis BMD system

with the SM-3 missile to shoot down an inoperable U.S. surveillance satellite that

was in a deteriorating orbit; or

flight tests of the Guam missile defense system.

Table A-1. Reported Aegis BMD Flight Tests From January 2002 to the Present

Date

Country

Name of flight

test of exercise

Ballistic Missile Target

Reported as

successful?

Exo-atmospheric (using SM-3 missile)

1/25/02

US

FM-2

Unitary short-range (TTV)

Yes

6/13/02

US

FM-3

Unitary short-range (TTV)

Yes

11/21/02

US

FM-4

Unitary short-range (TTV)

Yes

6/18/03

US

FM-5

Unitary short-range (TTV)

No

12/11/03

US

FM-6

Unitary short-range (TTV)

Yes

2/24/05

US

FTM 04-1 (FM-7)

Unitary short-range (TTV)

Yes

11/17/05

US

FTM 04-2 (FM-8)

Separating short-range (MRT)

Yes

6/22/06

US

FTM 10

Separating short-range (TTV)

Yes

12/7/06

US

FTM 11

Unitary short-range (TTV)

No

4/26/07

US

FTM 11

Event 4

Unitary short-range (ARAV-A)

Yes

6/22/07

US

FTM 12

Separating short-range (MRT)

Yes

8/31/07

US

FTM-11a

Classified

Yes

11/6/07

US

FTM 13

Unitary short-range (ARAV-A)

Yes

Unitary short-range (ARAV-A)

Yes

12/17/07

Japan

JFTM-1

Separating short-range (MRT)

Yes

11/1/08

US

Pacific Blitz

Unitary short-range (ARAV-A)

Yes

Unitary short-range (ARAV-A)

No

11/19/08

Japan

JFTM-2

Separating short-range (MRT)

No

7/30/09

US

FTM-17

Unitary short-range (ARAV-A)

Yes

10/27/09

Japan

JFTM-3

Separating short-range (MRT)

Yes

10/28/10

Japan

JFTM-4

Separating short-range (MRT)

Yes

4/14/11

US

FTM-15

Separating intermediate range (LV-2)

Yes

9/1/11

US

FTM-16 E2

Separating short-range (ARAV-B)

No

5/9/12

US

FTM-16 E2a

Unitary short-range (ARAV-A)

Yes

6/26/12

US

FTM-18

Separating short-range (MRT)

Yes

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Navy Aegis Ballistic Missile Defense (BMD) Program

Date

Country

Name of flight

test of exercise

10/25/12

US

FTI-01

Separating short-range (ARAV-B)

No

2/12/13

US

FTM-20

Separating medium-range (MRBM-T3)

Yes

5/15/13

US

FTM-19

Separating short-range (ARAV-C)

Yes

9/10/13

US

FTO-01

Separating medium-range (eMRBM-T1)

Yes

9/18/13

US

FTM-21

Separating short-range (ARAV-C++)

Yes

10/3/13

US

FTM-22

Separating medium-range (ARAV-TTO-E)

Yes

11/6/14

US

FTM-25

Separating short-range (ARAV-B)

Yes

6/25/15

US

FTO-02 E1

Separating medium-range (IRBM T1)

n/aa

10/4/15

US

FTO-02 E2

Separating medium-range (eMRBM)

n/ab

10/20/15

US

ASD-15 E2

Separating short-range (Terrier Orion)

Yes

11/1/15

US

FTO-02 E2a

Separating medium-range (eMRBM)

No

12/10/15

US (Aegis

Ashore)

FTO02 E1a

Separating medium-range (IRBM T1)

Yes

2/3/17

US-Japan

SFTM-01

Separating medium-range (MRT)

Yes

6/21/17

US-Japan

SFTM-02

Medium-range target

No

10/15/17

US

FS17

Medium-range target

Yes

1/31/18

US (Aegis

Ashore)

FTM-29

Intermediate-range target

No

9/11/18

Japan

JFTM-05

Simple separating target

Yes

10/26/18

US

FTM-45

Medium range target

Yes

12/10/18

US (Aegis

Ashore)

FTI-03

Intermediate-range target

Yes

11/16/20

US

FTM-44

ICBM target

Yes

5/26 and

30/2021

USNetherlands

ASD/FS21c

Non-separating MRBM target

Yesc

4/9/22f

US

FEM-01

Medium range target

Outcome not

reported

8/9/22

US

Part of Pacific

Dragon exercise

ARAV-B SRBM target

Yes

11/16/22e

US-Japan

JFTM-07

Medium-range T4-E target

Yes

11/18 or

19/22e

US-Japan

JFTM-07

Short-range target

Yes

10/25/23

US

Vigilant Wyvern/

FTM-48

Two short-range targets

Yes

2/8/24

US

FTX-23

Medium Range Ballistic Missile (MRBM)

target

Yes

Ballistic Missile Target

Reported as

successful?

Endo-atmospheric (using SM-2 missile Block IV missile and [for MMW E1 and subsequent] SM-6

Dual 1 missile)

5/24/06

US

Pacific Phoenix

Unitary short-range target (Lance)

Yes

6/5/08

US

FTM-14

Unitary short-range target (FMA)

Yes

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Date

Country

Name of flight

test of exercise

Ballistic Missile Target

Reported as

successful?

3/26/09

US

Stellar Daggers

Unitary short-range target (Lance)

Yes

7/28/15

US

MMW E1

Unitary short-range target (Lance)

Yes

7/29/15

US

MMW E2

Unitary short-range target (Lance)

Yes

12/14/16

US

FTM-27

Unitary short-range target (Lance)

Yes

8/29/17

US

FTM-27 E2

Medium-range target (MRBM)

Yes

5/29/21

US

FTM-31

Medium-range target (MRBM)

No

7/24/21

US

FTM-33

Two SRBM targets

Yes and

unconfirmedd

3/30/23

US

FTM-31 E1a

Medium-Range target (MRBM)

Yes (2-missile

salvo)

3/28/24

US

Stellar Laelaps/

FTM-32

Advanced Medium Range Ballistic Missile

(MRBM) target

Yes

Sources: Table presented in MDA fact sheet, “Aegis Ballistic Missile Defense Testing,” February 2017, accessed

on May 18, 2022, at https://web.archive.org/web/20170929180757/https:/www.mda.mil/global/documents/pdf/

aegis_tests.pdf, and (for flight tests subsequent to February 2017) MDA news releases, Jason Sherman, “U.S.

Intercepted Ballistic Missile Target over Pacific while China Exercised around Taiwan,” Inside Defense, August 12,

2022; and Wyatt Olson, “Missile-Defense Exercise Off Hawaiian Island Includes First Live-Fire Intercept,” Stars

and Stripes, August 16, 2022.

Notes: TTV is target test vehicle; ARAV is Aegis Readiness Assessment Vehicle. In addition to the flight tests

shown above, there was a successful use of an SM-3 on February 20, 2008, to intercept an inoperative U.S.

satellite—an operation called Burnt Frost.

a. MDA’s table shows this as a test that did not result in the launch of an SM-3. MDA as of August 3, 2015,

had not issued a news release discussing this event. MDA’s count of 31 successful intercepts in 37 launches

through July 29, 2015, does not appear to include this test, suggesting that this was considered a “no test”

event—a test in which there was a failure that was not related to the Aegis BMD system or the SM-3

interceptor. Press reports state that the test was aborted due to a failure of the target missile. (Andrea

Shalal, “U.S. Skips Aegis Ashore Missile Test After Target Malfunction,” Reuters, June 26, 2015.) MDA’s table

similarly shows the test of December 7, 2006, as a test that did not result in the launch of an SM-3. MDA

issued a news release on this test, which stated that an SM-3 was not launched “due to an incorrect system

setting aboard the Aegis-class cruiser USS Lake Erie prior to the launch of two interceptor missiles from the

ship. The incorrect configuration prevented the fire control system aboard the ship from launching the first

of the two [SM-3] interceptor missiles. Since a primary test objective was a near-simultaneous launch of two

missiles against two different targets, the second interceptor missile was intentionally not launched.” MDA

counts the test of December 7, 2006, as an unsuccessful intercept in its count of 31 successful intercepts in

37 launches through July 29, 2015.

b. MDA’s table shows this as a test that did not result in the launch of an SM-3. MDA as of November 10,

2015, had not issued a news release discussing this event. MDA’s count of 32 successful intercepts in 39

launches through November 1, 2015, does not appear to include this test, suggesting that this was

considered a “no test” event—a test in which there was a failure that was not related to the Aegis BMD

system or the SM-3 interceptor.

c. ASD/FS21 was an at-sea demonstration that occurred during a multilateral naval exercise called Formidable

Shield 2021. In the demonstration, a Dutch frigate used its radar to provide early warning track data to a

U.S. Navy destroyer that used the data to calculate a firing solution and launch its interceptor. Some press

reports state that ASD/FS21 involved two successful ballistic missile intercepts, rather than the one shown

in the table.

d. MDA stated that “based on initial observations, one target was successfully intercepted. At this time, we

cannot confirm the second target was destroyed.” (“MDA Test Intercepts Target,” MDA News Release 21NEWS-0012, July 24, 2021.)

e. A November 21, 2022, MDA new released stated: “The Japan Maritime Self-Defense Force (JMSDF) and the

United States Missile Defense Agency (MDA) announce the successful completion of a two-week missile

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f.

g.

defense event incorporating two live fire exercises.” (Missile Defense Agency, “Japan Missile Defense Flight

Test Successful,” 22-NEWS-0009, November 21, 2022.) Presss reports stated that two intercept events

occurred on November 16 and November 18 or 19. (Dzirhan Mahadzir, “Two Japanese Destroyers Score

in Ballistic Missile Defense Test off Hawaii,” USNI News, November 21, 2022; Rich Abott, “Japanese

Destroyers First Successfully Test SM-3 In Ballistic Missile Defense Test,” Defense Daily, November 22,

2022.)

For a press report about the SM-3 flight test of April 9, 2022, see Jason Sherman, “MDA Acknowledges

Clandestine SM-3 Block IIA Experiment of Classified Capability,” Inside Defense, January 26, 2023.

Author Information

Ronald O'Rourke

Specialist in Naval Affairs

Disclaimer

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Congressional Research Service

RL33745 · VERSION 263 · UPDATED

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