# Army Active Component (AC)/Reserve Component (RC) Force Mix: Considerations and Options for Congress

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/crs%3AR43808

## Record

- **Collection:** Congressional research report
- **Document type:** CRS Report
- **Published:** December 5, 2014
- **Citation:** R43808

## Text

Army Active Component (AC)/Reserve
Component (RC) Force Mix:
Considerations and Options for Congress
(name redacted)
Specialist in Military Ground Forces
(name redacted)
Specialist in Military Manpower Policy
December 5, 2014

Congressional Research Service
7-....
www.crs.gov
R43808

Army Active Component (AC)/Reserve Component (RC) Force Mix

Summary
The Army is composed of both an Active Component (AC) and a Reserve Component (RC). The
AC consists of soldiers who are in the Army as their full-time occupation. The RC is composed
primarily of soldiers who serve part-time but who can be ordered to full-time duty. The Army’s
RC is made up of both the Army National Guard (ARNG) and the United States Army Reserve
(USAR). AC/RC force mix refers to the distribution of units between the active and reserve
components of the armed forces.
The congressional role in AC/RC force mix is most obvious in its authorization of end strengths
for the active and reserve components of each Service. Congressional authority concerning
AC/RC mix, however, is much broader than that, as the Constitution provides Congress with
broad powers over the armed forces, including the power to “to raise and support Armies,” “to
provide and maintain a Navy,” “to make Rules for the Government and Regulation of the land
and naval Forces” and “to provide for organizing, arming, and disciplining the Militia, and for
governing such Part of them as may be employed in the Service of the United States.... ”
Debates over AC/RC mix center on whether or not to shift force structure between the AC and the
RC and, if so, what types of units to shift. Although specific force mix recommendations can be
nuanced, policy advocates generally divide between those who favor a stronger AC emphasis and
those who favor a stronger RC emphasis. In the contemporary debate, those who favor a stronger
RC emphasis believe that RC units, if properly trained and equipped, are as capable as their AC
counterparts while costing less. Thus, they argue that RC units can replace a portion of AC force
structure while saving money. Those who favor a stronger AC emphasis believe that certain RC
forces—particularly larger direct combat units and higher echelon headquarters—are not as
capable as AC forces without substantial additional preparation; cannot respond to a crisis as
rapidly as AC forces; and cannot be used with the same frequency and duration as AC forces due
to policy limitations. Those who take this perspective believe that replacing too many or certain
types of AC units with RC units could reduce the Army’s ability to respond rapidly to an overseas
crisis and sustain operations over time, or could require too much additional RC funding and
training time to make such an approach cost-effective.
Given the nation’s current fiscal situation, the contemporary debate has shifted somewhat in favor
of a higher ratio of RC forces. For example, in its FY2015 budget request, the Administration
proposes that RC forces make up 54.1% of the Army by FY2017, in comparison to 53.6% just
before the September 11 attacks and 49.1% when the Army was at its peak size during the Iraq
and Afghanistan wars (2010). This proposal would also include a shift of the relative proportion
of brigade combat teams (BCTs) towards the ARNG, although the Army’s Aviation Restructuring
Initiative proposes moving attack helicopters from the USAR and ARNG to the AC.
Determining the appropriate mix of AC and RC forces is complex, with many factors affecting
the process. Of these, utilization, readiness, effectiveness, cost, and risk are generally considered
the major elements in developing the AC/RC force mix. Each of these factors is described in
some detail in this report, along with questions for further investigation. As Congress considers
the future AC/RC mix for the Army, it may wish to consider several approaches, including
supporting Administration proposals on AC/RC mix; gathering additional information on key
factors which contribute to AC/RC mix decisions; directly altering AC/RC mix; and influencing
AC/RC mix by adjusting factors that contribute to mix decisions.

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Contents
Issue Overview ................................................................................................................................ 1
Importance to Congress ............................................................................................................. 1
A Brief History of Active Component (AC) and Reserve Component (RC) Force Mix ........... 3
Army Active-Reserve Mix ........................................................................................................ 7
Background ...................................................................................................................................... 8
Components of the Army........................................................................................................... 8
The Active Component (AC) .............................................................................................. 8
The Reserve Component (RC) ............................................................................................ 9
Basic Organization of Army Forces ........................................................................................ 10
The Army and the Other Services............................................................................................ 11
Army AC/RC Force Mix................................................................................................................ 14
How the Army Determines AC/RC Force Mix........................................................................ 14
Army Plans to Change its AC/RC Force Mix.......................................................................... 17
Smallest Acceptable Force Size ............................................................................................... 17
Potential Force Mix Scenarios................................................................................................. 17
What’s Missing in the Force Mix Discussion? ........................................................................ 18
Proposed Aviation Restructuring ............................................................................................. 18
AC/RC Mix: Considerations for Congress .................................................................................... 18
Utilization ................................................................................................................................ 18
Missions ............................................................................................................................ 19
Access to the Reserve Components................................................................................... 19
Deployment to Dwell (AC) and Mobilization to Dwell (RC) Ratios................................ 20
Key Questions Related to Utilization ................................................................................ 21
Readiness ................................................................................................................................. 21
The Army Readiness System............................................................................................. 22
Cyclical Readiness: The Army Force Generation (ARFORGEN) Model......................... 25
Comparing Readiness Between Units ............................................................................... 26
Key Questions Related to Readiness ................................................................................. 27
Effectiveness............................................................................................................................ 28
Key Questions Related to Effectiveness............................................................................ 29
Cost .......................................................................................................................................... 29
Which Costs Do You Count?............................................................................................. 29
How Should These Costs be Apportioned Between the Active and Reserve
Components? .................................................................................................................. 30
How Often Will Reserve Units Be Activated? .................................................................. 31
What is the Most Appropriate Way to Measure the “Output” of the Cost “Inputs”? ........ 31
Key Questions Related to Cost.......................................................................................... 34
Risk .......................................................................................................................................... 34
Key Questions Related to Risk.......................................................................................... 35
Other Considerations ............................................................................................................... 35
Options for Congress ..................................................................................................................... 36
Support Administration Proposals on AC/RC Mix.................................................................. 36
Obtain Additional Information ................................................................................................ 37
Direct New Studies............................................................................................................ 37
Establish Processes to Collect, Analyze, and Share New Types of Data .......................... 38
Directly Change the Force Mix ............................................................................................... 39
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Adjust End Strengths ......................................................................................................... 39
Reallocate Force Structure Between the AC and RC ........................................................ 39
Influence the Force Mix .......................................................................................................... 39
Reallocate AC and RC Roles and Missions ...................................................................... 39
Enhance Training for RC Units ......................................................................................... 40
Promote Greater Use of the RC......................................................................................... 42

Figures
Figure 1. The AC/RC Force Mix Process ...................................................................................... 16
Figure 2. Army Force Generation (ARFORGEN) Model ............................................................. 58

Tables
Table 1. Examples of Army AC/RC Force Mix ............................................................................... 8
Table 2. What Readiness Ratings Mean......................................................................................... 25

Appendixes
Appendix A. Aviation Restructuring Initiative (ARI) .................................................................... 44
Appendix B. Current Legislation Related to Army AC-RC Mix ................................................... 45
Appendix C. Historical Rationales for Reserve Forces ................................................................. 55
Appendix D. The Army Force Generation (ARFORGEN) Model ................................................ 57
Appendix E. Laws Governing Access to the Reserve Components .............................................. 59
Appendix F. Contemporary Studies on AC/RC Force Mix............................................................ 64
Appendix G. Individual Study Examinations................................................................................. 68

Contacts
Author Contact Information........................................................................................................... 93

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Issue Overview
The Army is composed of both an Active Component (AC) and a Reserve Component (RC). The
AC consists of soldiers who are in the Army as their full-time occupation. The RC consists
primarily of soldiers who serve part-time but who can be ordered to full-time duty. The Army’s
RC is made up of both the Army National Guard (ARNG) and the United States Army Reserve
(USAR). AC/RC force mix refers to the distribution of units among the active and reserve
components of the armed forces.1 Debates over AC/RC mix center on whether to shift force
structure between the AC and the RC and, if so, what types of units to shift. Although specific
force mix recommendations can be nuanced, policy advocates generally divide between those
who favor a stronger AC emphasis and those who favor a stronger RC emphasis. In the
contemporary debate, those who favor a stronger RC emphasis believe that RC units can replace a
portion of AC force structure while saving money. Those who favor a stronger AC emphasis
believe that replacing too many or certain types of AC units with RC units is not cost-effective
and could reduce the Army’s ability to respond rapidly to an overseas crisis and sustain operations
over time.

Importance to Congress
Typically, the details of AC/RC force mix are determined by the individual services within broad
parameters set by Congress, but Congress has sweeping power to set policy in this area. The
congressional role in AC/RC force mix is most obvious in its authorization of end strengths2 for
the active and reserve components of each Service, but congressional authority concerning
AC/RC mix is much broader than that.
The Constitution provides Congress with broad powers over the armed forces, including the
power to “to raise and support Armies,” “to provide and maintain a Navy,” “to make Rules for the
Government and Regulation of the land and naval Forces” and “to provide for organizing,
arming, and disciplining the Militia, and for governing such Part of them as may be employed in
the Service of the United States.... ”3 On the basis of its constitutional authority, Congress
authorizes and appropriates funds for the AC and RC on an annual basis and sets end strengths
limiting the size of the respective forces. Congress is also responsible for ensuring the AC and RC
are properly equipped and supplied, determining pay and benefits, establishing personnel policies,
and exercising oversight of Executive Branch management of the Department of Defense (DOD).
If it so chooses, it can also allocate roles and missions for the Services and their reserve
components, adjust reserve activation authorities, determine training regimens, establish or

1

Or, as an Army Information Paper states, “Active Component / Reserve Component (AC/RC) Force Mix is the term
used by the Army to articulate the distribution of force structure among the three Army components within established
End Strengths.” See Army Posture Statement, 2012, Addendum A, “Active Component/Reserve Component Mix,” at
https://secureweb2.hqda.pentagon.mil/VDAS_ArmyPostureStatement/2012/InformationPapers/ViewPaper.aspx?id=
229
2
The term “end strength” refers to the authorized strength of a specified branch of the military at the end of a given
fiscal year, while the term authorized strength means “the largest number of members authorized to be in an armed
force, a component, a branch, a grade, or any other category of the armed forces.” 10 USC 101(b)(11). As such, end
strengths are maximum personnel levels. Congress also sets minimum end strengths for the active components from
time to time, which may be identical to or lower than the maximum strength levels.
3
Article I, Section 8.

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disestablish units, specify unit composition, and designate the number and types of units within
each component.
In recent years, several factors have coincided to stimulate interest in the AC/RC mix, particularly
for the Army. The wars in Iraq and Afghanistan included large-scale and continuing mobilizations
of RC forces, and defense officials and other observers have generally expressed satisfaction with
the operational performance of these units. Additionally, concerns about federal spending,
coupled with the constraints of the Budget Control Act (BCA) of 2011 (P.L. 112-25), have led
many to look for ways to cut costs within the DOD. As a result, some policy makers have begun
considering whether part-time RC forces might provide a more cost-effective alternative to some
portion of the AC force structure, particularly for the Army, which has the largest reserve
component of all the Services.
In its FY2015 budget request, the Administration envisions shifting the AC/RC mix somewhat
more toward the RC. It proposes that RC forces make up 54.1% of the Army by FY2017, in
comparison to 53.6% just before the September 11 attacks and 49.1% when the Army was at its
peak size during the Iraq and Afghanistan wars (2010). This proposal would also include a shift
of the relative proportion of brigade combat teams (BCTs) towards the ARNG, although the
Army’s Aviation Restructuring Initiative proposes moving attack helicopters (AH-64 Apaches)
from the USAR and ARNG to the AC to replace retiring armed reconnaissance helicopters (OH58D). In return, the USAR and ARNG would receive utility helicopters (UH-60 Blackhawk).
Others have advocated a greater shift towards the RC. For example, one proposal put forward by
the National Guard Association of the United States recommends the Army be realigned so that
RC forces make up 58% of the Army, with 420,000 AC, 385,000 ARNG and 195,000 USAR.4
This discussion is not purely academic, as various groups favoring the RC or the AC attempt to
persuade the Administration and Congress of the importance and relevance of their respective
components in relation to what they believe will be the future strategic environment facing the
United States.
The House Armed Services Committee Oversight Plan for the 113th Congress summarized the
importance of this issue to Congress, and the difficult choices it poses, noting:
The debate that began during the 112th Congress about the most appropriate force structure
mix of active and reserve components, about the proper roles and missions of the reserve
components—be they an operational or strategic reserve—and about the affordability of the
required force to meet national security requirements will intensify in the 113th Congress.
Competition among the active and reserve components for diminishing resources will serve
as a catalyst for that debate. As evidenced by the debate about the Air Force's active and
reserve component force structure recommendations submitted with the Fiscal Year 2013
President’s budget and subsequent Congressional action, reaching a consensus will be most
challenging.5

4
National Guard Association of the United States, briefing entitled “The National Guard: Affordable Solution for a
Strong Defense,” slide 17 (“Solution 2- The Million Man Army). Two other proposals to increase the Army National
Guard by 10,000 and 20,000 personnel are put forward by Major General Wesley Craig in an article “A Better Course
of Action for the Army,” September 6, 2013, available at http://www.ngaus.org/blog/13/09/better-course-action-army
5
U.S. House of Representatives Committee on Armed Services 113th Congress Oversight Plan, undated, pp. 16-17.

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A Brief History of Active Component (AC) and Reserve
Component (RC) Force Mix
The ratio of AC and RC forces has shifted dramatically over time, and Congress has played a
central role in these shifts. From the founding of the nation to the Cold War era, the bulk of force
structure was maintained in the reserve component (especially the militia/National Guard), except
in times of major conflicts. When major conflicts arose—such as the Civil War, World War I, and
World War II—the comparatively small active component was expanded through the activation of
militia and federal reserves, recruitment of additional volunteers for the AC, and the use of
conscription.6 At the end of the conflict, active force levels were dramatically reduced. For
example, in 1939, there were fewer than 350,000 active duty personnel in all branches of the U.S.
armed forces. During World War II, this number grew enormously, reaching over 12 million
servicemembers on duty by 1945. With the end of World War II, the United States radically
reduced the size of its active armed forces to about 1.5 million in 1947-1950.
This approach changed with the onset of the Cold War. With the advent of the Korean War in
1950, the United States doubled the size of its active forces by 1951 to approximately 3.2 million.
This increase included a major reserve mobilization, with over 850,000 members of the National
Guard and Reserves called to active duty. However, with the end of the war in 1953, the size of
the active component did not decrease nearly as much as it would have in earlier eras. For the
next decade, it remained roughly between 2.5 million and 3 million for all services, while the size
of the reserve component hovered around 1 million. In response to the Vietnam War, the size of
the active component was increased again to about 3.5 million (1968), but there was no major
reserve mobilization.7 Thus, since the Korean War and continuing to the present, the United States
has maintained most of its force structure in the AC. (Although, it should be pointed out that
starting in 1989 and continuing to the present, a slight majority of Army force structure has been
RC.) In 2003, author Richard A. Lacquement Jr. noted:
Nevertheless, active duty forces dominate the military. This is unlike the peacetime history
of the U.S. armed forces before World War II when militia and other reserve forces far
outnumbered the much smaller standing elements of the armed forces ... Although there has
been a shift in relative emphasis to the ready reserves since the end of the Cold War, the
current American military posture is still dominated by the standing forces of the four
military services.8

This shift to an AC-centric force structure model in the aftermath of World War II began to ebb
somewhat starting in the 1970s. The downsizing that followed the Vietnam War, the end of the
6
Conscription in the United States did not begin until the Civil War, and it did not become a major source of military
manpower until World War I. The authority to use conscription lapsed in 1973.
7
Despite the United States’ substantial military involvement in Vietnam, only two comparatively minor reserve
activations occurred, both in 1968. The first reserve activation, announced on January 25, 1968, was not directly related
to the war in Vietnam. Rather, it was a response to the capture of the U.S. Navy intelligence ship Pueblo by North
Korea and the subsequent reinforcement of U.S. forces in South Korea. Most of the units activated remained in the
United States or were deployed to Korea, but some were stationed in Vietnam. The second reserve activation was
announced on April 11, 1968—just two months after the Tet Offensive in South Vietnam—and was intended “to meet
the needs of the Vietnam War and strengthen the depleted Active Strategic Reserve.” (Neil Sheehan,. New York Times.
“U.S. Calls 24,500 Reserves.” April 12, 1968, 1.) A total of 37,643 Guard and Reserve personnel were called up during
these activations.
8
Richard A. Lacquement Jr, “Shaping American Capabilities After the Cold War” 2003, p. 42.

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comparatively inexpensive manpower provided by conscription, budgetary pressures, and
dissatisfaction with the negative consequences of not using reserve forces more extensively
during Vietnam9 led to a renewed focus on using RC forces to supplement the AC. The Total
Force Policy, established in 1973 by Secretary of Defense James Schlesinger on the basis of the
1970 Total Force Concept developed by Secretary of Defense Melvin Laird, sought to integrate
“the Active, Guard and Reserve forces into a homogenous whole” and emphasized that, instead of
draftees, “Guard and Reserve forces will be used as the initial and primary augmentation of active
forces.”10
General Creighton Abrams, the Chief of Staff of the Army from 1972-74, implemented this policy
for the Army by instituting changes which deeply integrated reserve forces into the active force
structure. This deeper integration helped General Abrams rebuild the Army to 16 divisions while
staying within budgetary limits; it also effectively ensured that the Army could not be sent to war
again without the Guard and Reserve, as had occurred in Vietnam.11 The most notable
manifestation of this increased active-reserve integration was the roundout brigade program,
which involved restructuring of certain AC divisions to include an RC brigade. Normally, an AC
division would have three AC brigades assigned to it. At Abrams’ direction, some AC divisions
were assigned two AC brigades, along with a “roundout” National Guard brigade; other AC
divisions kept three AC brigades but had some of their AC battalions replaced with “roundout”
RC battalions. Congress passed a new law to allow in 1976 to make it easier for the President to

9

The war in Vietnam resulted in a major increase in the size of the Army, which grew from about 1 million soldiers in
1965 to about 1.5 million in 1969. This expansion was accomplished with almost no recourse to the Guard and
Reserve, as President Johnson repeatedly denied requests for major reserve mobilizations (the exception being two
comparatively minor mobilizations in 1968). One author of several historical works concerning the Vietnam era Army,
noted that “Failure to call the reserves at a time when the Army was necessarily expanding, and expanding hugely and
rapidly, had a devastating effect on the force. The pool of leaders was depleted over and over again to cadre new units,
with officers and non-commissioned officers being spread thinner and thinner. With the trained and experienced leaders
in the Reserve and National Guard out of reach, the Army was forced to promote its young officers and sergeants
prematurely, and to replace them with newly inducted and hastily trained substitutes.” Lewis Sorley, “Creighton
Abrams and Active-Reserve Integration in Wartime,” Parameters, Summer 1991, p. 38.
10
Memorandum from James Schlesinger, Secretary of Defense, “Readiness of the Selected Reserve,” August 23, 1973.
Emphasis in original.
11
For more on this, see Lewis Sorley, “Creighton Abrams and Active-Reserve Integration in Wartime,” Parameters,
Summer 1991, pp. 45-46. General Abrams restructured the Army in such a way as to make it very difficult for the
Army to conduct any significant deployment without mobilizing the Guard and Reserve, but there are differing
historical interpretations as to his intent in doing this. One perspective is that he did so at least in part to ensure that the
President and Congress could not commit the Army to a future conflict without the knowledge and implicit consent of
the American people, who would be more deeply impacted by a reserve mobilization than a war fought with only active
component personnel or conscripts. Lewis Sorley’s article, cited above, quotes several prominent Army officers who
worked with General Abrams and who support this interpretation. A critique of this perspective is summarized by
another author as follows: “Facing a significant drawdown, the shift to an all-volunteer armed force, and a desire for
ethical reform from the rank and file of an officer corps who believed the Vietnam war had weakened service integrity,
Abrams primary goals were to establish an active force structure that maintained 16 division flags while also increasing
the readiness of reserve components. His subordinates later claimed that he also had a long-term vision to ensure that
no president could ever again fight another Vietnam without mobilization, but that is not clear from available
documents. In fact, Secretary of Defense James Schlesinger considered the Army Chief of Staff the epitome of the
“good servant” who always deferred to civilian control of the military.” Conrad C. Crane, Avoiding Vietnam: The U.S.
Army's Response to Defeat in Southeast Asia (Carlisle, PA: Strategic Studies Institute, 2002), p. 5,
http://www.strategicstudiesinstitute.army.mil/pubs/display.cfm?pubID=58. Regardless of the motivation, it does not
appear that the Army’s reliance on its reserve component has been a significant barrier to the United States’ use of
military force, as demonstrated by substantial reserve activations in support of operations over the past 25 years (e.g.,.
Kuwait, Iraq, Bosnia, Kosovo, Haiti and Afghanistan).

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activate RC personnel and units.12 Other initiatives to improve active-reserve integration in the
1970s and 1980s included more modernized equipment for the RC, greater overseas training
opportunities, and rotations at the newly established National Training Center. 13
The first major test of this greater active-reserve integration came during the 1990-91 Persian
Gulf War, which saw the activation of over 238,000 RC personnel, including about 60,000
members of the Army National Guard and some 88,000 members of the Army Reserve.14 In many
respects, RC performance in this conflict strengthened support for the Total Force Policy among
defense policy makers.15 However, there were areas of RC readiness identified as needing
improvement. This was most apparent with respect to the roundout brigades.16 Three ARNG
roundout brigades were mobilized, somewhat belatedly, and deployed to the National Training
Center for post-mobilization training. Amid claims of serious readiness deficiencies, however,
they were not certified as combat ready until the war was over. A contemporary report by the
Congressional Research Service summarized this experience as follows:
In late 1990, three Army National Guard combat maneuver brigades were mobilized for
Operation Desert Shield (later Desert Storm), the U.S. military effort against Iraq. All three
brigades were “roundout” units, designated to bring an active Army division to full strength
upon mobilization. However, the brigades were not activated until four months after Desert
Shield began; the two whose parent divisions fought in the war did not deploy with those
divisions; none of the brigades left the U.S.; and the only one to be “validated” as combat
ready was so judged on the day of the cease-fire. The brigades' experience generated much
controversy about the viability of the roundout concept and the active Army's relationships
with the National Guard ... The major criticism of the roundout brigades is that they were not
ready to deploy with their parent divisions. However, roundout brigades were never intended
to deploy without some postmobilization training, and it was never envisioned that they
could deploy immediately in response to a no-notice crisis. Unfortunately, a combination of
excessive optimism, overreliance on numerical readiness ratings, and high-level inattention
to the actual readiness levels of the roundout brigades before Desert Shield/Storm led many
to assume that they were as ready as similar active Army brigades. Although the brigades
had major readiness problems when first called up, they were able to be validated for
12

This statute, originally codified at 10 USC 673b, formed the basis for what is today known as Presidential Selected
Reserve Call Up authority (10 USC 12304).
13
Michael Doubler and Vance Renfroe, “The National Guard and Total Force Policy,” in The Modern National Guard
(Tampa, FL: Faircount LLC, 2003), pp. 42-47.
14
The total number of reservists mobilized for Operation Desert Shield/Storm was 238,729, broken out by reserve
component as follows: Army Reserve (88,282), Army National Guard (60,350), Naval Reserve (19,461), Air Force
Reserve (22,860), Air National Guard (10,456), Marine Corps Reserve (35,671), and Coast Guard Reserve (1,649). See
CRS Report RL30637, Involuntary Reserve Activations For U.S. Military Operations Since World War II, by (name red
acted).
15
The report which accompanied the House version of the National Defense Authorization Act for FY1993 stated “The
committee recommends a package of reforms designed to pave the way for an expanded role for combat units in the
future ... Operation Desert Storm provided a great deal of information about mobilizing and using the reserve
component. Although the experience revealed much that worked very well, it also pointed out the need for some
necessary changes in the Army National Guard, as well as the active Army.” U.S. Congress, House Committee on
Armed Services, Report of the Committee on Armed Services, House of Representatives, on H.R. 5006 , 102nd Cong.,
2nd sess., May 19, 1992, H.Rept. 102-527 (Washington: GPO, 1992), p. 19.
16
The General Accounting Office published several reports which were fairly critical of the brigades’ readiness,
including U.S. General Accounting Office, Peacetime Training Did Not Adequately Prepare Combat Brigades for Gulf
War, NSIAD-91-263, September 24, 1991, http://www.gao.gov/products/NSIAD-91-263 and U.S. General Accounting
Office, Army Guard Combat Brigade War Lessons Reflect Long-Standing Problems, T-NSIAD-92-36, May 5, 1992,
http://www.gao.gov/assets/110/104510.pdf.

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deployment to the theater of war three months after activation. This was an unprecedented
achievement compared with past call ups of similar reserve component units. 17

The Persian Gulf War experience led Congress to address identified readiness shortcomings
through passage of the Army National Guard Combat Readiness Reform Act of 1992 (also known
as “Title XI,” in reference to its location within the 1993 National Defense Authorization Act18).
The reforms focused primarily, though not exclusively, on ARNG combat units. Title XI
contained 19 provisions which sought to improve the readiness of Army Guard units and their
compatibility with AC units by: increasing experience and leadership levels in the ARNG by
recruiting more prior-service personnel, Service Academy graduates, and ROTC graduates;
revising the training focus for combat units; providing for a more robust medical and dental
evaluation process; ensuring the compatibility of personnel, supply, maintenance and finance
systems across the AC, ARNG, and USAR; reforming the Army’s readiness system for USAR and
ARNG units; directing the Secretary of the Army to conduct inspections to ensure that ARNG
units meet deployability standards; and mandating that the Army provide greater funding to early
deploying ARNG and USAR units.19
Although the Department of Defense effectively ended the roundout brigade program in 1993,20
the disintegration of the Soviet Union gave further impetus to the ongoing integration of the AC
and RC. With the demise of the United States’ main military competitor, the requirement for large
numbers of ground forces at a high state of readiness was considered less critical for national
security. Subsequently, AC force structure was substantially reduced in the 1990s. During this
time, the Army also adjusted the roles of its reserve components. The Army’s 1993 “Offsite
Agreement”21 guided the realignment of force structure between the ARNG and USAR, and
stipulated that
•

The ARNG would retain a balanced mix of combat and support units;22

•

The USAR would be divested of nearly all its combat structure and would focus
on providing support units; it would also provide the bulk of the RC’s Echelon
Above Division (EAD) and Echelon Above Corps (EAC) units; and

•

The USAR and ARNG would swap approximately 12,000 spaces to facilitate this
agreement.

17

(name redacted), CRS Report to Congress, “The Army’s Roundout Concept After the Persian Gulf War,” October
22, 1991, summary page. See also Anne W. Chapman, The National Training Center Matures, 1985-1993, U.S. Army
Training and Doctrine Command Military History Office, Fort Monroe, VA, 1997, pp. 237-248,
http://www.tradoc.army.mil/HISTORIAN/publications.htm and Michael D. Doubler, Civilian in Peace, Soldier in War:
The Army National Guard, 1636-2000 (Lawrence , KS: University Press of Kansas, 2003), pp. 312-317, 330-332.
18
P.L. 102-484.
19
P.L. 102-484, Title XI (sections 1101-1137).
20
Michael D. Doubler, Civilian in Peace, Soldier in War: The Army National Guard, 1636-2000 (Lawrence , KS:
University Press of Kansas, 2003), pp. 349-50.
21
Some information about the Offsite Agreement provided to CRS during a meeting with the Army G-8 office on May
19, 2014.
22
In the terminology common at that time, the ARNG would continue to maintain a balanced mix of combat, combat
support (CS), and combat service support (CSS) units, while the USAR would be made up almost exclusively CS and
CSS units. Combat units include infantry, armor, artillery, special forces and certain aviation and engineer units.
Combat support (CS) includes intelligence, communication, chemical, military police and certain aviation and engineer
units. Combat service support (CSS) includes supply, ordnance, transportation, medical, legal, and finance units.

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The post-Cold War drawdown was followed by the increased employment of RC forces in Iraq
(low-intensity conflict with Iraq, 1998-2003), Bosnia (1995-2004), Kosovo (1999-present), and
Haiti (1994-1996). As the use of RC units increased and they gained experience through
repetitive deployments, the distinction between components faded somewhat, and RC units began
to be more seriously considered as suitable substitutes for AC units—provided they received
necessary personnel, equipment, training and preparation time prior to being deployed. This
perspective was further reinforced by the large-scale and continuing mobilizations of RC forces
for the wars in Iraq and Afghanistan, which led many public officials and policy analysts to
conclude that the performance of the RC in these conflicts largely validated the Total Force
Policy. Some Army officials have argued, however, that AC and RC units are not interchangeable,
with one senior Army officer indicating that this was the reason RC BCTs were used for less
complex missions in Iraq and Afghanistan than their AC counterparts.23 RC advocates counter
that they had no control over the missions they were assigned in Iraq and Afghanistan, that they
were effective in all the missions they were given, and that they could have successfully
completed combined arms maneuver missions if they had been given the opportunity.24
In addition to the large scale mobilization of RC units during the wars in Iraq and Afghanistan,
Congress authorized significant expansions of the active Army and Marine Corps. This led to an
increase in the ratio of AC to RC forces in those Services. However, with the end of the war in
Iraq and the ongoing reduction of forces in Afghanistan, a multi-year drawdown of AC forces is
underway in these Services. This drawdown has rolled back the war-time increases in AC strength
and will likely end at a level lower than existed prior to the war. As such, the proportion of AC to
RC forces will also likely decline in those Services.

Army Active-Reserve Mix
The Army determines the distribution of units between the AC, ARNG, and USAR within the end
strengths25 mandated annually by Congress by a process it calls Total Army Analysis (TAA). The
TAA uses a deliberative campaign analysis process to determine the demand for forces from all
three components based on multiple possible future scenarios and current operational demands, as
well as lessons learned from past operations and conflicts and resource constraints. AC/RC force
mix is dynamic and changes over time in response to changing national security strategies and the
resources made available to the Army. Table 1 illustrates the changing nature of AC/RC force
23
See comments of Major General John Rossi, Army Quadrennial Defense Review Director, in Sydney J. Freedberg,
Jr., Breaking Defense, “National Guard Commanders Rise in Revolt Against Active Army; MG Rossi Questions Guard
Combat Role,” available at http://breakingdefense.com/2014/03/national-guard-commanders-rise-in-revolt-againstactive-army-mg-ross-questions-guard-combat-role/. Chief of Staff of the Army Raymond Odierno made similar if less
specific comments at the National Press Club on January 7, 2014: “ ... the Army for many years now is structured to
become complementary. And what I mean by that is you have an active component that has a certain capability. You
have a National Guard that has a certain capability. And you have a U.S. Army reserve that has a certain capability.
The capabilities are not interchangeable. There's a reason why the active component is more expensive. It brings you a
higher level of readiness because they're full-time. They are trained and ready to do things at a higher level because
they spend every day focused on that. Our National Guard, who's done an incredible job in the last 10 years, trains 39
days a year. And that covers personnel training and—so when you're talking about integrating organizationally, it takes
a bit longer. So it's not—they're not interchangeable.”
24
See also National Guard Association of the United States, “NGAUS: Guard and Active Units are ‘Interchangeable,’”
January 13, 2014, available at http://www.ngaus.org/newsroom/news/ngaus-guard-and-active-units-areinterchangeable#
25
See footnote 2 for the definition of end strength.

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mix. Of all the Services, the Army has the largest reserve component, and the highest ratio of
reserve component personnel to active component personnel.
Table 1. Examples of Army AC/RC Force Mix
K = thousands; M = millions
Year

AC Levels

RC Levels

AC % of
force mix

RC % of
force mix

Total Size
of Army

1989 (end of the Cold War)

770 K

776 K

49.1%

50.1%

1.546 M

Sept 11, 2001

480 K

555 K

46.4%

53.6%

1.035 M

2010 (peak Army strength
related to wars in Iraq and
Afghanistan)

570 K

564 K

50.3%

49.7%

1.134 M

FY2015 Budget Request

490 K

552 K

47.0%

53.0%

1.042 M

Army proposal for FY2017
(“smallest acceptable force”)

450K

530K

45.9%

54.1%

980K

Army proposal for FY2019
(“worst case scenario”)

420K

500K

45.6%

54.4%

920K

Source: Historical data, Army budget documents, and information given to CRS during a meeting with the Army
G-8 office on May 19, 2014.
Note: The Army has the highest proportion of its force structure in the RC (52% at the end of FY2014). For
comparative purposes, the RC proportions for the other Services at the end of FY2014 are as follows: Navy
(15%), Air Force (35%), Marine Corps (17%).

Background
Components of the Army
The Army has an Active Component and two Reserve Components: the Army National Guard and
the Army Reserve. These three components are sometimes identified as Compo 1 (Active Army),
Compo 2 (Army National Guard), and Compo 3 (Army Reserve). Each component is discussed in
more detail below.

The Active Component (AC)
The Army’s active component consists of soldiers who are in the Army as their full-time
occupation. Soldiers in the AC can be deployed world-wide with little to no advanced notification
to participate in a wide variety of military operations. The AC has both direct combat and
support-type units. Examples of the former include infantry, armor, artillery, combat aviation, and
special forces units; while the latter include medical, transportation, communications, supply,
ordnance, intelligence, military police, and engineer units.

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The Reserve Component (RC)
The term “Reserve Component” normally refers to all seven of the individual reserve components
of the Armed Forces,26 but for the purpose of this report it refers only to the Army’s reserve
components: the Army National Guard of the United States and the United States Army Reserve.
The purpose of the reserve components, as codified in law, is to “provide trained units and
qualified persons available for active duty in the armed forces, in time of war or national
emergency, and at such other times as the national security may require, to fill the needs of the
armed forces whenever more units and persons are needed than are in the regular components.”27
A DOD directive further states: “It is DOD policy that... The RCs provide operational capabilities
and strategic depth to meet U.S. defense requirements across the full spectrum of conflict.... ”28
The Army National Guard also has a state role, described below.

Army National Guard (ARNG)
Descended from colonial-era militias29 which existed prior to the adoption of the Constitution, the
Army National Guard has a long historical pedigree. The Constitution contains provisions that
recognize the existence of the militia and that granted the federal government a certain amount of
control over it.30 Additionally, since 1933, the ARNG has been not only a part of the organized

26
The seven reserve components are the Army National Guard of the United States, the Army Reserve, the Navy
Reserve, the Marine Corps Reserve, the Air National Guard of the United States, the Air Force Reserve, and the Coast
Guard Reserve. Although the term “reserves” is often used as a generic term to refer to all members of the seven
individual reserve components, there is an important distinction between the five reserve components that are purely
federal entities (the Army Reserve, Navy Reserve, Marine Corps Reserve, Air Force Reserve, and Coast Guard
Reserve) and the two reserve components that are both federal and state entities (the Army National Guard and the Air
National Guard). Hence, in some contexts, the five purely federal reserve components are referred to collectively as the
Reserves, while the dual federal/state reserve components are referred to as the National Guard.
27
10 U.S.C. 10102. The language was changed by P.L. 108-375, the Ronald W. Reagan National Defense
Authorization Act for FY2005. Prior to this change, the language was as follows: “The purpose of each reserve
component is to provide trained units and qualified persons available for active duty in the armed forces, in time of war
or national emergency, and at such other times as the national security may require, to fill the needs of the armed forces
whenever, during and after the period needed to procure and train additional units and qualified persons to achieve the
planned mobilization, more units and persons are needed than are in the regular components.” The change in statutory
language, as explained in a House Armed Services Committee report, would “clarify that the purpose of the reserve
components is to provide trained units and qualified personnel not just as the result of involuntary mobilizations but
whenever more units and persons are needed than are in the active component. The revision recommended by this
section more accurately reflects recent and future employments of the reserve components.” H.Rept. 108-491, p. 316.
28
Department of Defense Directive 1200.17, “Managing the Reserve Components as an Operational Force,” October
29, 2008, paragraph 4a, available at http://www.dtic.mil/whs/directives/corres/pdf/120017p.pdf .
29
The colonial militia, which was derived from a longstanding English tradition and which required every able bodied
free male (though Native Americans and free blacks were frequently excluded) to participate in the common defense of
his town or locality, was the principal institution of colonial military power. Gradually, as the colonial population grew
and military threats waned, a distinction arose between the unorganized militia (those members of the militia who were
potentially liable for military service but who did not actively participate in military training) and the organized militia
(those members of the militia who regularly trained for war and who responded first to military threats). Today, the
U.S. Code still recognizes the militia as consisting of “all able-bodied males at least 17 years of age and ... under 45
years of age who are, or who have made a declaration of intention to become, citizens of the United States and of
female citizens of the United States who are members of the National Guard.” (10 U.S.C. 311) This provision of the
law further divides the militia into the organized and the unorganized militia, and declares the National Guard and the
Naval Militia to be the organized militia. At present New York, Ohio, and South Carolina have active Naval Militias.
30
See U.S. Constitution, Article I, Section 8, clauses 15 and 16, and Article II, Section 2, clause 1.

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militia of the various states, but simultaneously a reserve component of the Army. In this latter
status, it falls under Congress’ broader constitutional authority “to raise and support Armies.”31
This unique history means that the ARNG is both a federal and a state organization. It is made up
of 54 separate National Guard organizations: one for each state, and one each for Puerto Rico,
Guam, the U.S. Virgin Islands, and the District of Columbia. While the District of Columbia
National Guard is an exclusively federal organization and operates under federal control at all
times, the other 53 National Guards operate as state or territorial organizations most of the time.
In this capacity, each of these 53 organizations is identified by its state or territorial name (e.g.,
the California National Guard or the Puerto Rico National Guard), and is controlled by its
respective governor. Due to their dual federal and state role, National Guardsmen can be called to
duty in several different ways.
The ARNG is made up primarily of part-time personnel who are usually required to train at least
one weekend a month and two weeks per year. Training time can be increased if needed; for
example, if an individual needs to attend a military school, or if the unit is preparing for
deployment. The ARNG also has a cadre of full-time support personnel, who are “assigned to
organize; administer; instruct; recruit and train; maintain supplies, equipment and aircraft; and
perform other functions required on a daily basis in the execution of operational missions and
readiness preparations as authorized in Title 5 [Government Organizations and Employees], Title
10 [Armed Forces], and Title 32 [National Guard].... ” The full-time cadre makes up about 17%
of the total strength of the ARNG. During times of war and in support of other military missions,
the ARNG can be federalized and deployed. It also participates in a wide variety of other
activities such as assisting during natural disasters or supporting homeland security operations,
although it typically does these missions while under the control of the state governor. Like the
AC, the ARNG has both direct combat and support type units.

United States Army Reserve (USAR)
In comparison to the ARNG, the USAR is of comparatively recent origin, having been established
in 1908 under Congress’s constitutional authority “to raise and support Armies.”32 It is a purely
federal entity and today is composed almost exclusively of support units rather than direct combat
units. Like the ARNG, the USAR consists primarily of part-time soldiers who are usually required
to train at least one weekend a month and two weeks per year, although training time can be
increased if needed. The part-time personnel are augmented by a cadre of full-time support
personnel, who constitute about 14% of total USAR strength. Unlike the ARNG, which normally
operates under state control, the USAR is always under the control of the federal government.

Basic Organization of Army Forces
The Army—whether AC or RC component—is organized along the following basic lines:
How the Army Organizes its Forces
Squad – 4 to 12 soldiers

31
32

U.S. Constitution, Article 1, Section 8, clause 12.
U.S. Constitution, Article 1, Section 8, clause 12.

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From an operational perspective, the Army
focuses on the brigade level. Brigades have
the capacity to be employed independently on
operations as they possess organic
headquarters, combat, combat support, and
combat service support units. Brigades can be
combined along with other units to form
divisions. Divisions, along with a variety of
higher echelon support units, can be combined
into corps and armies, which are well suited
for large scale, long-duration operations.

Platoon – 16 to 50 soldiers
Company – 60 to 200 soldiers
Battalion – 400 to 1,000 soldiers
Brigade – 3,000 to 5,000 soldiers
Division – 10,000 to 18,000 soldiers
Corps – 40,000 to 100,000 soldiers
Army – 100,000 to 300,000 soldiers

The Focus on Army Brigades
From a 2012 RAND Report:
“In 2003, the U.S. Army began implementing a set of ambitious changes to its force structure to address the
challenges of waging war and conducting extended stabilization operations. A key change involved transitioning the
Army from a traditional, division-based force into a brigade-based force, a concept that has come to be known as
"modularity." Some important capabilities that were formerly part of the host division were made organic to the
brigade combat team organization. The Army also reduced the range of combat brigade types from 17 to three:
infantry, Stryker, and Heavy [now referred to as Armored] ... The move to modularity provided the Army with a
greater number of smaller, very capable force packages, making it easier to sustain the protracted operations in Iraq
and Afghanistan. Combat support and combat service support units and force structure were also redesigned to make
the entire force more modular.” 33

Types of Army Brigades
Brigade Combat Teams: Armored Brigade Combat Teams (ABCTs); Stryker Brigade Combat Teams (SBCTs);
and Infantry Brigade Combat Teams (IBCTs), including airborne, air assault, and light infantry variations; and.
Functional and Multi-Functional Support Brigades: Aviation, Fires (artillery, etc.), Air Defense, Intelligence,
Battlefield Surveillance, Cyber, Engineer, Maneuver Enhancement, Chemical, Biological, Radiological, Nuclear and
Explosive (CBRNE), Military Police, Civil Affairs, Medical, Transportation, Field Support, Sustainment, and
Contracting.

The Army and the Other Services
The Army is not a stand-alone service but instead part of a joint team. This relationship is
described in the following passage.
Although individual Services may plan and conduct operations to accomplish tasks and
missions in support of Department of Defense (DOD) objectives, the primary way DOD
employs two or more Services (from two Military Departments) in a single operation,
particularly in combat, is through joint operations. Joint operations is the general term to
describe military actions conducted by joint forces and those Service forces in specified
command relationships with each other.34

33

Stuart E. Johnson, John E. Peters, Karin E. Kitchens, Aaron Martin, Jordan R. Fischbach, “A Review of the Army’s
Modular Force Structure,” RAND National Defense Research Institute, 2012, p. iii.
34
Joint Publication 1, Doctrine for the Armed Forces of the United States, March 23, 2013, p. xi.

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The Army’s most significant role as part of the joint force is the provision of landpower, further
defined as:
The Army’s contribution to joint operations is landpower. Landpower is the ability—by
threat, force, or occupation—to promptly gain, sustain, and exploit control over land,
resources, and people. Landpower includes the ability to—
- Impose the Nation’s will on adversaries—by force if necessary—in diverse and complex
terrain.
- Establish and maintain a stable environment that sets the conditions for a lasting peace.
- Address the consequences of catastrophic events—both natural and manmade—to restore
infrastructure and reestablish basic civil services.
- Support and provide a base from which forces can influence and dominate the air and sea
dimensions of the joint operational area.
While the Army is an integral part of the joint force, the value of its contribution depends on
its ability to exercise landpower. Ultimately, Army forces’ ability to control land, resources,
and people through a sustained presence makes permanent the advantages gained by joint
forces.35

It should also be noted the Army provides critical enabling capabilities to joint operations
including joint command and control (Joint Force Headquarters), communications, air and missile
defense, and logistics.
Functions of the Department of the Army
a. The Department of the Army includes land combat, and service forces, and such aviation, water transport, and
space and cyberspace forces as may be organic therein, and shall be organized, trained, and equipped primarily for
prompt and sustained combat incident to operations on land, and to support the other Military Services and joint
forces. The Army is responsible for the preparation of land forces necessary for the effective prosecution of war and
military operations short of war, except as otherwise assigned. The Army is the Nation’s principal land force and
promotes national values and interests by conducting military engagement and security cooperation; deterring
aggression and violence; and should deterrence fail, compelling enemy behavioral change or compliance. The Army
shall contribute forces through a rotational, cyclical readiness model that provides a predictable and sustainable supply
of modular forces to the Combatant Commands, and a surge capacity for unexpected contingencies.
b. The Functions of the Army. In addition to the common military service functions listed in paragraphs 2.a. through
2.n. of this enclosure, the Army, within the Department of the Army, shall develop concepts, doctrine, tactics,
techniques, and procedures, and organize, train, equip, and provide forces with expeditionary and campaign qualities
to perform the following specific functions:
(1) Conduct prompt and sustained combined arms combat operations on land in all environments and types of
terrain, including complex urban environments, in order to defeat enemy ground forces, and seize, occupy, and
defend land areas.
(2) Conduct air and missile defense to support joint campaigns and assist in achieving air superiority.
(3) Conduct airborne and air assault, and amphibious operations. The Army has primary responsibility for the
development of airborne doctrine, tactics, techniques, and equipment.
(4) Conduct CAO [civil affairs operations].

35

Field Manual 1, The Army, June 2005, p. 1-1.

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(5) Conduct riverine operations.
(6) Occupy territories abroad and provide for the initial establishment of a military government pending transfer
of this responsibility to other authority.
(7) Interdict enemy sea, space, air power, and communications through operations on or from the land.
(8) Provide logistics to joint operations and campaigns, including joint over-the-shore and intra-theater transport
of time-sensitive, mission-critical personnel and materiel.
(9) Provide support for space operations to enhance joint campaigns, in coordination with the other Military
Services, Combatant Commands, and USG departments and agencies.
(l0) Conduct authorized civil works programs, to include projects for improvement of navigation, flood control,
beach erosion control, and other water resource developments in the United States, its territories, and its
possessions, and conduct other civil activities prescribed by law.
(11) Provide intra-theater aeromedical evacuation.
(12) Conduct reconnaissance, surveillance, and target acquisition.
(13) Operate land lines of communication.36

Types of Army Operations
The Army conducts what is described as “full spectrum operations.”
During joint campaigns overseas, Army forces execute a simultaneous and continuous combination of offensive,
defensive, and stability and reconstruction operations as part of integrated joint, interagency, and multinational
teams. Concurrently with overseas campaigns, Army forces within the United States and its territories combine
offensive, defensive, and civil support operations to support homeland security. Strategically, the ability to
conduct offensive, defensive, and stability and reconstruction operations in overseas campaigns while
supporting homeland security domestically is central to full spectrum operations.37
Specific operations types described in the preceding paragraph are defined as:
•

Offensive operations carry the fight to the enemy by closing with and destroying enemy forces, seizing
territory and vital resources, and imposing the commander's will on the enemy. They focus on seizing, retaining,
and exploiting the initiative.38

•

Defensive operations counter enemy offensive operations. They defeat attacks, destroying as many attackers
as necessary. Defensive operations preserve control over land, resources, and populations. They retain terrain,
guard populations, and protect key resources. Defensive operations also buy time and economize forces to allow
the conduct of offensive operations elsewhere. Defensive operations not only defeat attacks but also create the
conditions necessary to regain the initiative and go on the offensive or execute stability and reconstruction
operations.39

•

Stability and reconstruction operations sustain and exploit security and control over areas, populations, and
resources. They employ military capabilities to reconstruct or establish services and support civilian agencies.
Stability and reconstruction operations involve both coercive and cooperative actions. They may occur before,
during, and after offensive and defensive operations; however, they also occur separately, usually at the lower

36

Department of Defense Directive 5100.01, Functions of the Department of Defense and Its Major Components,
December 21, 2010.
37
Ibid.
38
Ibid.
39
Ibid.

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end of the range of military operations. Stability and reconstruction operations lead to an environment in which,
in cooperation with a legitimate government, the other instruments of national power can predominate.40
•

Within the United States and its territories, Army forces support homeland security operations. Homeland
security operations provide the Nation strategic flexibility by protecting its citizens and infrastructure from
conventional and unconventional threats. Homeland security has two components. The first component is
homeland defense. If the United States comes under direct attack or is threatened by hostile armed forces,
Army forces under joint command conduct offensive and defensive missions as part of homeland defense. The
other component is civil support, which is the fourth type of Army operation.41

•

Civil support operations address the consequences of man-made or natural accidents and incidents beyond
the capabilities of civilian authorities. Army forces do not conduct stability and reconstruction operations within
the United States; under U.S law, the federal and state governments are responsible for those tasks. Instead,
Army forces conduct civil support operations when requested, providing Army expertise and capabilities to lead
agency authorities.42

A central tenet of full spectrum operations is that all Army units—AC and RC alike—are required to be ready to
successfully conduct all of the aforementioned operations.

Army AC/RC Force Mix
How the Army Determines AC/RC Force Mix43
The starting point for determining AC/RC force mix is a series of national security strategic
guidance documents including the following:
•

The Administration’s National Security Strategy (NSS);

•

DOD’s National Defense Strategy (NDS);

•

The congressionally-mandated Quadrennial Defense Review (QDR); and

•

The Chairman of the Joint Chiefs of Staff’s (CJCS) National Military Strategy
(NMS).44

These high-level strategic documents broadly articulate the Army’s role in the national security
architecture. They also delineate specific missions and responsibilities as well as parameters that
the Army uses to help determine what kind of force the Army needs to “build.” Based on these
documents the Army could build a heavier (more armor) or lighter (more infantry) force, a force
oriented on fighting a major regional adversary, or one that is more focused on counterinsurgency,
etc. However, because there is risk associated with putting too much emphasis on one type of
force (heavy vs. light, for example), the Army tends to build a mix of forces that can address a
wide variety of operations—or what the Army refers to as a “full spectrum” force.

40

Ibid.
Ibid.
42
Ibid.
43
Information in this table is taken from information given to CRS during a meeting with the Army G-8 office on May
19, 2014.
44
For detailed information on the aforementioned national security documents see CRS Report R43174, National
Security Strategy: Mandates, Execution to Date, and Issues for Congress, by (name redacted).
41

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In addition to strategic guidance, budgetary considerations play a major role in determining the
size of the Army as well as, to an extent, the AC/RC force mix. Historically, during times of
conflict or national emergency, resources are made available to expand the Army as well as
provide necessary equipment and training. After conflicts or during periods of protracted peace,
traditionally fewer resources have been provided to the Army, often resulting in a drawdown of
forces as well as the rebalancing of the AC/RC mix based on the premise that RC forces are less
costly to maintain during peacetime. These decreases in resources can also adversely affect the
readiness of available forces as well as impact Army modernization efforts.

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Figure 1. The AC/RC Force Mix Process
From Conception to Employment

Source: CRS graphic developed by authors.

As previously noted, the Army determines much of the AC/RC force mix by the Total Army
Analysis (TAA) process. TAA generates the combat support (CS) and combat service support
(CSS) forces needed to support divisional and non-divisional combat forces that are set forth in
the Defense Planning Guidance (DPG). The TAA uses a deliberative campaign analysis process to
determine the demand for forces from all three components based on multiple possible future
scenarios, current operational demands, as well as lessons learned from past operations and
conflicts, and resource constraints. This force is then presented to Army leadership who use the

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approved force to build the Army’s annual budget request. Figure 1 graphically depicts the
process used to determine the Army’s AC/RC force mix.

Army Plans to Change its AC/RC Force Mix
In addition to overall force size, the Army also expresses AC/RC force mix in terms of units, with
the brigade combat team (BCT)45 being the most commonly used unit. Brigade combat teams
(BCTs) are the Army’s basic operational warfighting unit and it should be noted there are only AC
and ARNG BCTs—the USAR has no BCTs. As the Army reduces overall force size, the force
mix between AC and RC is altered to reflect these reductions. In FY2014, the Army has:
•

38 Active Component BCTs.

•

28 Army National Guard BCTs.

•

66 Total BCTs.

In 2013, the Army decided to add an additional “maneuver battalion”46 to its Infantry BCTs and
Armored BCTs which, prior to 2013, had only two maneuver battalions (unlike Stryker BCTs
which have always had 3 maneuver battalions). This additional maneuver battalion will come
from BCTs in the process of deactivating. Thus, even though BCTs are being eliminated from AC
and RC force structure, Infantry and Armored BCTs are gaining additional combat capability
which should be taken into consideration when discussing force reductions and force mix.

Smallest Acceptable Force Size47
The Army has stated a 450,000 AC, a 335,000 ARNG, and a 195,000 USAR—28 active BCTs
and 24 ARNG BCTs (52 BCTs total)—is the “smallest acceptable force to implement the defense
strategy.” Any force smaller than this “lacks the capacity to conduct simultaneous major combat
operations while defending the nation at home, sustaining minimal presence in critical regions,
and retaining a Global Response Force (consisting of one BCT) at the direction of the
Commander-in-Chief.” 48

Potential Force Mix Scenarios49
The Army has stated that force structure reductions are required to meet sequestration-imposed
funding levels. The Budget Control Act (BCA) of 2011 (P.L. 112-25), as amended by the
American Taxpayer Relief Act of 2012 (P.L. 112-240), requires across-the-board spending
45

For additional information on brigade combat teams see CRS Report R42493, Army Drawdown and Restructuring:
Background and Issues for Congress, by (name redacted).
46
Maneuver battalion is an Army term for either an infantry or armored (tank) battalions which are capable of
“maneuvering” to destroy enemy forces.
47
Information in this section is taken from an Army Briefing, “Army Force Mix: Least Risk: Best Value,” January 6,
2014.
48
Ibid. p. 3.
49
Information in this section is taken from an Army Briefing, “Army Force Mix: Least Risk: Best Value,” January 6,
2014. For more detailed information on the Army’s drawdown see CRS Report R42493, Army Drawdown and
Restructuring: Background and Issues for Congress, by (name redacted).

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reductions (sequestration) in most federal defense and nondefense discretionary programs. The
American Taxpayer Relief Act of 2012 raised defense and nondefense budget spending limits
under the Budget Control Act (BCA) for FY2014 and FY2015 but BCA spending limits will
return in FY2016 if no further legislative action is taken.
Because of budget uncertainty, the Army’s “worst case” planning scenario is that sequestrationlevel funding levels return in FY2016. In addition, DOD has provided the Army with both
strategic and fiscal guidance which influences the force level the Army can “afford” as well as the
AC/RC force mix. Under this worst case scenario, the Army would reduce in size to a 420,000
AC; a 315,000 ARNG; and an 185,000 USAR which would translate to 24 AC BCTs and 22
ARNG BCTs. Army leadership has repeatedly stated that this force level would result in
insufficient capacity and the Army would be unable to implement the U.S. defense strategy.

What’s Missing in the Force Mix Discussion?
As previously noted, BCTs are the mostly commonly portrayed unit type when examining AC/RC
force mix but there are scores of other types of units ranging from combat aviation brigades,
engineer units, logistics units, to military police brigades as well as smaller units that are part of
the greater force mix equation. These non-BCT formations play a significant role in a wide range
of military operations and depending on the operation, they could be the focus of the operation
instead of BCTs. It is important to note that when determining AC/RC force mix, these non-BCT
units are also included as part of the process even though they are frequently not included in
related discussions. In this regard, when questioning Army AC/RC force mix proposals, it could
prove beneficial to also examine the mix of non-BCT units as well.

Proposed Aviation Restructuring
In March 2014, the Army proposed a plan (referred to as the Aviation Restructuring Initiative or
ARI) to restructure aviation units. Under the ARI, the AC and National Guard would be allocated
aircraft that supposedly better align with each component’s respective missions which would also
supposedly generate savings. This proposal, which has generated a great deal of discussion, is
further discussed in Appendix A.

AC/RC Mix: Considerations for Congress
Determining the appropriate mix of AC and RC forces is complex, with many factors affecting
the process. Of these, utilization, readiness, effectiveness, cost, and risk are generally considered
the major elements in developing the AC/RC force mix. These factors are all linked to the ability
of the specified military forces to meet national security requirements in a budget constrained
environment. However, there are other factors often considered with respect to AC/RC mix,
particularly with respect to the National Guard. These factors are discussed briefly as well, under
the heading “Other Considerations.”

Utilization
A key driver of Army force structure, both AC and RC, is the anticipated future demand for Army
units. What will they be used for? How quickly will they need to respond? For how long will they

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be needed? Answering these questions involves assumptions about likely threats to national
interests, how frequently the United States will deploy Army units in response to those threats,
and what type of mission they will need to conduct when responding to those threats. Given those
broad parameters, several factors should be considered in determining how much of the
“demand” can be met with AC forces and with RC forces.

Missions
The missions anticipated for Army units play a key role in determining the number and types of
units the Army maintains in its force structure. If AC and RC units of the same type are identical
in capability and availability, they can be used in precisely the same manner and, consequently,
this factor would have limited applicability to AC/RC mix considerations. However, some
observers argue AC and RC units are not identical in terms of availability and, at least in some
circumstances, are not identical in terms of capability; hence, they are not always interchangeable
for mission planning purposes. For example, AC Army units are usually considered better
positioned to respond to crises requiring immediate action because they are more readily
available; that is, they typically require less notification, preparation and train up time prior to
deployment than similar RC units.50 RC Army units tend to be preferred for missions that permit a
substantial train up period; for example, as reinforcements for an initial response force or as part
of a periodic rotation for a long term mission. Additionally, given policy constraints on the length
of RC activations (discussed more below), AC units are often preferred for “forward presence”
missions overseas, such as the main Army forces in Europe and South Korea. More controversial
is the contention that AC and RC units of the same type are not identical in terms of their
capability. (See footnote 23) Some argue that AC units are superior to their RC counterparts in
certain respects, and are therefore better suited for certain missions—most notably high intensity
combat or “combined arms maneuver.”51 The reverse of this argument—that some RC units are
better suited to certain missions (such as homeland defense, disaster response, and missions with
a close civilian analogue)—is also advanced.

Access to the Reserve Components
Historically, one of the barriers to use of the RC was the limited circumstances under which they
could legally be ordered to active duty. The principal activation authorities in effect after World
War II—today known as Full Mobilization and Partial Mobilization Issues—limited reserve
activations to times of war or situations where a national emergency had been declared by
Congress or the President. In 1976, a new authority, now known as Presidential Reserve Callup
Authority, allowed the President to activate reservists for missions without a declaration of
50
Several factors relate to this: more rapid assembly of an active personnel (versus the time it takes to invoke activation
authorities for reservists and assemble the personnel); the full-time nature of active duty allows AC soldiers to maintain
a higher state of training readiness (whereas reserve soldiers typically need at least some post-mobilization training);
the location of AC units on bases which have support activities to enable deployment (whereas RC units frequently
have to travel some distance to arrive at such a base); and, more AC units are forward deployed and may thus be
located closer to the crisis location.
51
The Army’s doctrinal definition of combined arms maneuver is “the application of the elements of combat power in
unified action to defeat enemy ground forces; to seize, occupy, and defend land areas; and to achieve physical,
temporal, and psychological advantages over the enemy to seize and exploit the initiative. It exposes enemies to
friendly combat power from unexpected directions and prevents an effective enemy response.” Department of the
Army, Army Doctrinal Publication 3-0, Unified Land Operations, October 10, 2011, p. 6, available at
http://armypubs.army.mil/doctrine/DR_pubs/dr_a/pdf/adp3_0.pdf .

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emergency, though the duration of this type of activation was limited, as was the number of
reservists who could be activated at any given time. Subsequent amendments expanded the scope
of this authority significantly. The FY2012 National Defense Authorization Act added two new
activation authorities: one to permit activation of reservists for up to 120 days to respond to
disasters, and another to permit activation of reservists for up to one year for “preplanned mission
in support of a combatant command.” This latter authority opens the door for activations in
support of more routine military missions, rather than the crisis or “contingency” focus of the
other authorities. These activation authorities are summarized in Appendix E.
The lowering of legal barriers to reserve activations has contributed to the increased use of
reservists in recent decades and eased the concerns of senior defense officials that reservists will
be available when needed. Still, when considering whether to use reserve forces in a given role or
for a particular mission, the reserve activation authorities place constraints on defense officials
that do not exist for active forces. In particular, there are statutory limits on the number of
reservists that may be activated, and the length of time that they may be ordered to active duty.
Since 2007, there have also been DOD policy limitations on the frequency and duration of reserve
activations that are stricter in certain respects than the statutory limits (discussed in the next
section). Finally, in considering the use of reserve units for specific roles and missions, defense
planners must take into account the time it takes to invoke activation authorities for reservists,
notify affected units, assemble their personnel, and conduct post-mobilization training.

Deployment to Dwell (AC) and Mobilization to Dwell (RC) Ratios52
During World War II, Army units typically deployed for the duration of the conflicts; thus, units
and their personnel could spend three to four years deployed in combat zones. A different
approach was used starting with the Korean War, when individuals were rotated in and out of
theater on a periodic basis. During the Vietnam conflict, soldiers were rotated in and out of the
deployed unit for a one year “tour of duty” and then returned home. While this policy addressed
the issue of spending an extended period in combat, it also created a great deal of turbulence
which some cited as having had an adverse impact on unit cohesion and discipline.
With the advent of the All-Volunteer Force and the growth of military families, separating
soldiers from their families for extended periods raised concerns about impacts on retention.
When it became apparent to military leadership that operations in Iraq and Afghanistan would
span many years, DOD established a deployment policy for the Active and Reserve components.
In 2007, the Secretary of Defense established a “deployment-to-dwell” policy for AC forces—
which remains in effect today—indicating that the planning objective would be one year of
deployment followed by two years at home station. He also limited RC activations to a maximum
of one year (excluding individual skill training and post-mobilization leave), and set the
“mobilization to dwell” planning objective for RC units at one year mobilized followed by five
years demobilized.53 These dwell time policies are typically expressed by the ratios of 1:2 and
1:5.

52
Information from this section is taken from Secretary of Defense Memorandum, “Utilization of the Total Force,
January 19, 2007.
53
Memo from Secretary of Defense Robert Gates, “Utilization of the Total Force,” January 19, 2007, available at
http://www.armyg1.army.mil/MilitaryPersonnel/Hyperlinks/Adobe%20Files/
OSD%20Memo%20dtd%2020070119%20-%20Utilization%20of%20the%20Force.pdf

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In addition to the differences in ratios, another key distinction between the two policies is that the
deployment-to-dwell ratio for AC units is tied only to time deployed, while the mobilization to
dwell ratio for RC units is tied to time mobilized, which can include both pre-deployment training
and deployment time. For example, a one-year mobilization for an RC unit might include three
months of train up followed by a nine-month deployment. These differences in policy for AC and
RC units play a critical role in comparative cost estimates which use a deployed unit cost
approach (discussed later in the report).

Key Questions Related to Utilization
•

What are the major threats to which Army units will be expected to respond?
How fast will the Army be expected to respond and with what types of units?
How long will operations last? How long will units be expected to remain in a
deployed status. Will units need to conduct multiple deployments in order to
meet sustained demands?

•

Are there any roles or missions for which either AC or RC forces are clearly
more capable than their counterpart, and therefore might be the preferred force of
choice? How does this determination align with current AC and RC force
structure?

•

Should statutory limits in reserve activation authorities be modified? Should they
allow more reservists to be activated, and for a longer period of time, than
currently allowed?

•

Should the DOD policy on “deployment-to-dwell” ratios be modified for active
and/or reserve personnel? If so, what should those ratios look like? Are they
sufficiently robust to meet projected national security obligations? Do they allow
sufficient rest time between deployments so that recruiting and retention remain
at acceptable levels?

Readiness
Readiness is a term policy makers, analysts, and military leaders often cite when describing the
state of the U.S. military. The Department of Defense defines readiness as “the ability of military
forces to fight and meet the demands of assigned missions.”54 There are two processes currently
in place for reporting the readiness of military units: the Department of Defense Readiness
Reporting System (DRSS) and the Chairman’s Readiness System (CRS). This report will focus
on the way in which Army commanders determine the readiness of their units to perform their
“core functions/designed capabilities”55 for submission to DRSS. The data for DRSS comes from
a report known as the Commanders Unit Status Reports (CUSR) or Unit Status Reports (USR),
which unit commanders submit to the Army component of DRSS (known as DRSS-Army or
DRSS-A).

54

Department of Defense, Joint Publication 1-02, Department of Defense Dictionary of Military and Associated Terms,
as amended through July 16, 2014, p. 214, available at http://www.dtic.mil/doctrine/new_pubs/jp1_02.pdf .
55
There is a separate, though similar process, for reporting readiness for a unit’s “assigned mission,” as an assigned
mission may vary somewhat from what the unit was designed to do.

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The Army Readiness System
Readiness can be evaluated in different ways, but Army readiness evaluations revolve around four
main components: personnel, equipment availability, equipment readiness, and training, each
of which is described below. This readiness evaluation process is led by unit commanders, who
assess readiness levels within the parameters specified by Army regulations. Sometimes the
regulations require the commander to apply professional military judgment to a significant degree
(most notably in the case of training assessments); while in other areas the commander’s
discretion is much more limited.

Personnel (P-level)
There are three principal measures of personnel readiness (“P-level metrics”) for Army units:
1. The ratio of unit personnel available for deployment in comparison to the total
number of personnel the unit is authorized to have.
2. The ratio of unit personnel who are both available for deployment and qualified
in their assigned duty position in comparison to the total number of personnel the
unit is authorized to have.
3. The ratio of available “senior personnel” in comparison to the total number of
senior personnel the unit is authorized to have.
Ratios in each of these metrics generate a rating between 1 (highest) and 4 (lowest) according to a
published scale, and the lowest of these three ratings is used to determine the overall “P-rating” of
the unit.56 In essence, units with a full or nearly full complement of soldiers by specialty and
grade are assessed as P-1, while those with substantial shortages in one or more of the measured
areas are assessed as P-2, P-3, or P-4, depending on how significant the shortfalls are. This aspect
of readiness is relatively objective and therefore requires limited application of a commander’s
professional judgment.

Equipment Availability (S-level)
Another readiness factor for Army units is the availability or supply of key equipment. This is
called the “S-level,” and it is based on two metrics:
1. The ratio of designated critical equipment items (known as pacing items)
currently in the unit’s possession, under its control, or available within 72 hours
in comparison to the number of such items the unit is authorized to have. For
example, a pacing item for an armor unit would be M-1 Abrams tanks.
2. The ratio of other mission essential equipment items57 currently in the unit’s
possession, under its control, or available within 72 hours in comparison to the
number of such items the unit is authorized to have. Examples of this type of
equipment might include radios, machine guns, and night vision devices.

56
57

That is, if the three personnel metrics are rated as 1, 1, and 2, respectively, the P-level will be P-2.
These items are designated as “Equipment Readiness Code A” or ERC A.

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Like the P-level, ratios in each of these metrics generate a rating of between 1 and 4 according to
a published scale, and the lowest of these two ratings is used to determine the overall “S-rating”
of the unit.58 Units with all or nearly all of their most important equipment are assessed as S-1,
while those with substantial shortages in pacing items or other mission essential equipment are
assessed as S-2, S-3, or S-4, depending on how significant the shortfalls are. This aspect of
readiness is readily measurable.
Equipment availability is heavily influenced by whether there is sufficient funding to procure the
required equipment for a given unit, and by how senior policy makers chose to allocate
equipment among units. In the Cold-War era, RC units had comparatively low S-level ratings, as
senior defense officials considered equipping these units to be a lower priority than equipping AC
units. This changed significantly with the wars in Iraq and Afghanistan and the large-scale and
ongoing mobilization of RC units. In 2013, according to the Department of Defense, AC units had
approximately 91% of their authorized equipment on hand, the ARNG had approximately 91%,
and the Army Reserve had approximately 86%.59

Equipment Readiness (R-level)
The third measured area for Army units is equipment readiness or serviceability. That is, is the
unit’s equipment fully functional or not? A unit could have all of its authorized equipment by type
and numbers, but still suffer from poor equipment readiness if a large portion of authorized
equipment or weapon systems does not work. The “R-level” is determined by calculating the
percentage of each pacing item that is fully mission capable, and the aggregate percentage of
certain designated equipment (“maintenance reportable equipment”) in the unit’s possession that
is fully mission capable. Each of these categories is rated between 1 and 4 according to a
published scale, and the lowest of these ratings becomes the overall R-level.
The R-level is heavily influenced by funding. If there is not enough money for spare parts or to
send a vehicle into depot level maintenance, equipment readiness can suffer. Unit manning can
affect equipment readiness too. If there are not enough trained mechanics and supply personnel,
repairs can be delayed. RC units have full-time support personnel dedicated to equipment
maintenance, and the number of these personnel have increased since the wars in Iraq and
Afghanistan began. However, some argue that RC full-time manning levels are still less than
optimal.

Training (T-level)
The final measured area for Army readiness is the most subjective, and relates to training.
Training readiness does not lend itself to quantifiable evaluation to the same extent as personnel
and equipment readiness, and so relies more heavily on the commander’s professional military
judgment. In assessing training readiness, unit commanders evaluate how well trained the unit is
on certain key tasks, known as “mission essential tasks” or METs. Commanders evaluate their
unit’s training proficiency in each MET as either trained (T), needs practice (P), or untrained (U).
58

That is, if the two equipment metrics are rated as 1 and 3, respectively, the S-level will be S-3.
Office of the Assistant Secretary of Defense for Reserve Affairs, Deputy Assistant Secretary of Defense (Materiel
and Facilities), National Guard and Reserve Equipment Report for FY2015, March 2014, pp. 2-3, available at
http://ra.defense.gov/Portals/56/Documents/NGRER%20FY2015.pdf . The figures refer to MTOE (Modified Table of
Organization and Equipment) units, which are units designed for deployment.
59

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Based on these ratings, a specified calculation methodology, and a published scale, the unit
receives a T-level rating of between 1 and 4.60
An important tenet of training readiness is that all units—AC and RC—train to the same
standards. However, AC and RC units do not necessarily achieve proficiency at the same
organizational level (i.e., platoon, company, battalion, or brigade). During the ARFORGEN cycle,
RC units are typically funded to achieve platoon or company level proficiency prior to
deployment, while AC units are often funded to achieve battalion or brigade level proficiency
prior to deployment (see “Differences in ARFORGEN Training Levels” later in the report).
Additionally, the data on which the commander’s judgments are made can vary substantially. For
example, there may be variations between units in the frequency of training, the ranges and
resources available for the training, and the number and type of units represented in a training
exercise. Operational deployments may also be used when evaluating a unit’s training
proficiency, so the commander of a recently deployed unit may be able to more accurately assess
his or her unit’s training status.

Overall Readiness (C-level)
The C-level rating, or overall readiness assessment, is derived from the four areas discussed
above (P, S, R & T). The C-level is equivalent to the lowest of these four levels,61 although
commanders have some ability to upgrade or downgrade the rating based on their professional
military judgment. The C-rating is meant to reflect the unit’s ability to accomplish its core
functions, provide its designed capabilities, and carry out its mission essential tasks.62 The
meaning of each C-level is described in Table 2.

Subjective Upgrades and Downgrades
Army commanders may not upgrade or downgrade the ratings of the four main resource
categories (i.e., they cannot upgrade or downgrade the P, S, R, or T ratings). However, under
certain circumstances, commanders may upgrade or downgrade the “C-level” rating of their unit.
They do this by comparing the C-level rating initially determined with the descriptions outlined in
Army Regulation 220-1, which are summarized in Table 2. If the two are mismatched in the
commander’s professional judgment, he or she may upgrade or downgrade the unit’s C-level
rating so it more closely aligns with the appropriate C-level description. Commanders of brigades
and smaller organizations may upgrade or downgrade the C-level by one rating level on their own
authority; changes of two rating levels require approval of a higher ranking commander of a
specified rank. Commanders of divisions and corps headquarters may upgrade or downgrade by

60

The methodology assigns a weight of 3 to each “T,” 2 to each “P,” and “1” to each U. These figures are summed and
then divided by the product of 3 multiplied by the number of METs. The resulting quotient is multiplied by 100 to
produce a percentage, which is interpreted according to a published scale. As an example, if a unit had 5 METs, which
the commander evaluated as T, P, T, U, and P this would be converted to 3, 2, 3, 1, and 2. The sum of these numbers
(3+2+3+1+2=11) would then be divided by the 3 times the number of METs (3x5=15). The resulting percentage would
be 73.3% (11/15*100). If the unit had no untrained tasks (U), this percentage would result in a T-2 rating. However,
since the unit has an untrained task, the result is a T-3 rating.
61
That is, if the unit was evaluated as P-1, S-1, R-1, and T-3, it would receive a C-3 rating, subject to the possible
upgrade or downgrade by the commander.
62
AR 220-1, para4-4(a).

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up to two levels on their own authority. The commander must explain the rationale for any such
subjective change.
Table 2. What Readiness Ratings Mean
For Army “C-Level” Ratings
C-1

C-2

C-3

The unit possesses the
required resources and is
trained to accomplish or
provide the core
functions and
fundamental
capabilities for which it
was designed.

The unit possesses the
required resources and is
trained to accomplish or
provide most of the
core functions and
fundamental
capabilities for which it
was designed.

The unit possesses the
required resources and is
trained to accomplish or
provide many, but not
all, of the core
functions and
fundamental
capabilities for which
was designed.

The status of resources
and training in the unit do
not limit flexibility in
methods to accomplish
core functions.

The status of resources
and training in the unit
may cause isolated
decreases in the
flexibility of choices to
accomplish core functions.
.

The status of resources
and training in the unit will
result in significant
decreases in flexibility
to accomplish core
functions.

The status of resources
and training in the unit will
not increase vulnerability
of unit personnel and
equipment.

The status of resources
and training in the unit will
not increase the
vulnerability of the unit
under most envisioned
operational scenarios

The status of resources
and training in the unit will
increase the vulnerability
of the unit under many,
but not all, envisioned
operational scenarios.

The unit does not
require any
compensation for
deficiencies.

The unit will require
little, if any,
compensation for
deficiencies.

The unit will require
significant
compensation for
deficiencies.

C-4

The unit requires
additional resources or
training to accomplish or
provide the core
functions and
fundamental
capabilities for which
was designed.

Source: Adapted from AR 220-1, paragraph 4-6. Emphasis added to highlight the differences between ratings.

Other Measures of Readiness
The metrics discussed above are considered the most important measures of readiness by the
Army, but they do not encompass all the ways of measuring readiness. Certain other measures of
readiness are also available to commanders to inform any decision to upgrade or downgrade their
readiness ratings. For example, Army databases provide information on personnel turnover rates,
additional skill qualifications, language qualifications, and professional military education
completion. Other measures of readiness—for example, discipline, morale, and certain aspects of
leadership and experience—while typically considered important aspects of unit readiness, are
not formally integrated into the readiness assessment process. However, commanders may take
these factors into account in their C-level upgrade/downgrade decisions.

Cyclical Readiness: The Army Force Generation (ARFORGEN) Model
Because the Army has limited resources, its units cannot all be maintained at the highest state of
readiness (C-1) at the same time. One way of doing this is called “tiered readiness,” with

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designated units continually maintained in the highest state of readiness, with the remainder
maintained at lower readiness levels. This technique was used during the Cold War era, with
many AC units and nearly all RC units normally maintained in lower readiness states; this
approach assumed that there would be sufficient time and resources to improve their readiness in
the event of a major conflict. The reduction in AC force structure at the end of the Cold War,
coupled with the pressures of the wars in Iraq and Afghanistan, generated a need to share the
burden of deployment among more Army units. Additionally, the Army also began to use its
reserve units with greater frequency and so invested more resources in improving and
maintaining the readiness of RC units.
Because the Army cannot maintain all of its forces at the highest state of readiness, a process is
needed to bring units in a lesser state of readiness to a high state of readiness so they can be
deployed to conduct full spectrum operations. The current process the Army employs is known as
Army Force Generation (ARFORGEN), a cyclical readiness system that applies to both the AC
and RC. Appendix D provides additional details on the ARFORGEN process.

Differences in ARFORGEN Training Levels
Discussions with the Army staff63 indicate that AC BCTs enter the Available Pool trained up to
the brigade level, meaning the unit is ready to be deployed and conduct full spectrum operations
as a brigade. In contrast, ARNG BCTs are only trained up to the platoon and company level prior
to mobilization, meaning that only that BCT’s platoons and companies are ready for full-spectrum
operations. Additional resources and authorized training days could enable ARNG BCTs to train
to a higher level prior to mobilization, or they can conduct additional train up during postmobilization training. Nonetheless, the disparity in training readiness has significant implications
for the employment of ARNG BCTs in certain operations, particularly those that are complex or
short-to-no-notice. Other types of RC units, such as separate battalions and companies, may
achieve the same training levels as their AC counterparts prior to mobilization.

Comparing Readiness Between Units
The Defense Readiness Reporting System is intended to broadly assess the ability of military
forces to fight and meet the demands of assigned missions, as illustrated in Table 2. Thus, two
units with a C-1 rating—whether AC or RC—should both have the required resources and
training proficiency to accomplish all of their core functions, without significant limitations on
their flexibility of methods or increases in unit vulnerability. However, in some circumstances this
is not necessarily the case. Some possible examples include
•

The training area relies on a subjective application of professional military
judgment. Might there be cases in which some commanders overestimate the
training status of their unit while others underestimate it? This could be due to a
variety of factors, including having served more or less time as a commander,
having observed more or fewer unit training events, having undergone more or
less challenging training scenarios, or having a more or less critical attitude
towards judging training outcomes.

63

Information in this section is taken from information given to CRS during a meeting with the Army G-8 office on
May 19, 2014.

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•

The P, S, and R-level ratings are meant to be fairly objective, but they do not
claim to represent all possible readiness factors. Other factors that could
significantly affect the ability of a unit to accomplish its core functions might
include unit discipline and morale, amount of time key personnel have served in
their positions, and the leadership abilities of commissioned and
noncommissioned officers in the unit. Might disparities in these unmeasured
factors affect the comparability of unit readiness ratings? Commanders have the
authority to incorporate such factors with their upgrade/downgrade authority for
C-level ratings, but the use of this authority is subjective and may admit to
substantial variation between commanders.

•

Variations in experience may not be fully captured in the P-level ratings. The Plevel rating attempts to capture experience by determining if a person with the
right grade and occupational specialty is filling each authorized position in the
unit. It also attempts to capture experience by determining if there are an
adequate number of people of senior grade, in comparison to the number of
authorized senior positions. However, both of these metrics use grade (rank) as a
proxy for experience, rather than experience itself. This is not unreasonable given
that grade is closely tied to years of military service; but years of active military
service normally produce more military experience than do years of reserve
military service. Additionally, civilian experience is not captured at all by these
metrics. As such, P-level ratings may not fully capture experience, and the ratings
might overlook key differences in the experience of AC and RC personnel.

Key Questions Related to Readiness
•

Do the readiness levels of AC and RC units differ in general, or in certain types
of units? If so, what factors are associated with this difference? How might any
such differences be ameliorated?

•

Are readiness ratings directly comparable between AC and RC units?

•

With respect to the subjective areas of readiness assessment, particularly training
assessments and upgrades/downgrade, are there differences in the way AC and
RC commanders make their determinations?

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Effectiveness
As discussed above, the Defense Readiness
Reporting System (DRRS) is designed to
assess the ability of units to “execute their
missions, plans, and individual tasks based on
their capabilities reflecting demonstrated
performance in training and operations.” 64
Logically then, readiness levels should
correlate strongly with actual unit
performance during exercises and operational
missions. However, CRS was unable to find
any studies which attempted to determine the
extent of this correlation. There does not
appear to be any systematic assessment of unit
performance during the wars in Iraq and
Afghanistan that would be suitable for
comparing unit effectiveness between AC and
RC units.

Differences in AC and RC Experience
Two of the P-level metrics—qualified in duty position
and senior level personnel—consider whether the grade
(rank) of a given individual corresponds to the doctrinally
required grade of the position they occupy in a unit. The
required grade for the position is essentially a proxy for
required experience level. This is reasonable given that
military grade is closely tied to years of military service
(experience); but years of active military service normally
produce more military experience than do years of
reserve military service, given that active service is fulltime and reserve duty is often part-time. Additionally,
civilian experience is not captured at all by these metrics.
Hence, a lieutenant colonel or master sergeant with 18
years of active military service will have substantially
greater military experience than a lieutenant colonel or
master sergeant with 18 years of reserve service. This
differential is not captured by the relevant P-level
metrics. On the other hand, the lieutenant colonel or
master sergeant with 18 years of reserve service may
also have 18 years (or more) of civilian experience that is
equivalent to or superior to that of his active duty
counterpart. This differential is not captured either.

The National Defense Authorization Act for
FY2012 included a provision requiring the
Department of Defense to submit a report
“setting forth an analysis of the costs of a
sample of deployable units of the active components of the Armed Forces and the costs of a
sample of similar deployable units of the reserve components of the Armed Forces.” DOD
submitted this report to Congress on December 20, 2013, and it was subsequently evaluated by
the Government Accountability Office (GAO). The GAO assessment of the DOD report included
the following statement:
Second, the report does not consider or comment on the effectiveness of either active- or
reserve-component units when compared to each other. DOD officials told us that there are
differences across the services in the way that reserve-component units are employed, so it
would be difficult to generalize about their relative effectiveness. The officials told us that it
is a generally accepted principle that in most cases, similar active and reserve units should
have comparable levels of effectiveness after completing sufficient training; however, they
added that data for measuring active- and reserve-unit effectiveness are limited and
inconsistently collected. Because the report does not include a discussion of active- and
reserve-unit effectiveness, the extent to which the unit-cost comparisons presented in the
report can be used to inform force-mix decisions is limited.65

The “generally accepted principle” discussed above that “similar active and reserve units should
have comparable levels of effectiveness after completing sufficient training” makes intuitive
sense, but it does raise some pertinent questions. For example:
•

64
65

What is meant by “sufficient training”—the amount of training that AC and RC
units currently receive during the ARFORGEN process or something different?

AR 220-1, para 2-5(c ).
http://www.gao.gov/assets/670/665181.pdf

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•

Do RC units currently receive “sufficient training” prior to deployment to make
them comparable in effectiveness to AC units? If not, how much additional
training, and what types of training, would be required to make RC units
comparable to AC units in effectiveness?

•

Do variations in AC and RC training practices disadvantage RC units? If so, are
there ways to align RC training practices more closely with AC practices so as to
provide more comparable levels of training?

•

What impact, if any, do differences in the military and civilian experience of AC
and RC personnel play in the comparative effectiveness of AC and RC units?

Key Questions Related to Effectiveness
•

Are AC and RC units with the same readiness levels equally effective in
exercises and operational missions?

•

Are there certain missions or types of units where AC units are more effective
than RC units due to training or experience differentials, and vice-versa?

•

Does AC and RC unit effectiveness vary by echelon (i.e., company, battalion, and
brigade)? If so, are there ways to mitigate these differences?

Cost
A key consideration for policy makers when considering AC/RC mix is their comparative cost.
Which are less expensive: AC units or RC units? From one perspective, the answer appears
obvious: an RC unit that is not activated is inherently less expensive than a similar AC unit,
because the large majority of RC personnel only perform military duty part-time, whereas AC
personnel perform military duty full-time. This difference also affects comparative training and
equipment maintenance costs. Additionally, even when an RC unit is activated, its cost should be
roughly equivalent to a similar AC unit, as comparable AC and RC units have nearly identical
equipment and personnel authorizations. Various studies have approached the issue of AC/RC
costs from this perspective, and come up with different determinations of the size of the cost
differential. The differences hinge on three principal factors: (1) the range of costs being
considered, (2) the apportionment of those costs between the AC and RC, and (3) assumptions
about how often RC units will be in an inactive status versus an active status. Each of these points
is discussed below. Additionally, some studies have approached AC/RC costs from a different
perspective, one that focuses on the different “outputs” associated with those costs. From this
perspective, RC units are not always less expensive than AC units, and in some cases they can be
more expensive, because multiple RC units are needed to match the output of one AC unit. This
perspective is summarized below as well.

Which Costs Do You Count?
An important factor in evaluating AC and RC costs relates to which costs to count. When
comparing Army, Army Reserve, and Army National Guard costs, some analyses look only at
personnel costs, or only at personnel costs plus operations and maintenance costs. This disregards
other costs, such as military procurement, research and development, and construction costs. A
more expansive approach looks at the “top-line” budget figure for the Army, the Army Reserve,
and the Army National Guard. However, even this approach is not comprehensive as it omits

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certain costs covered by DOD, such as those associated with health care and commissaries. It also
excludes military-related costs covered by other agencies, such as the costs of Veterans’ Affairs
educational, disability, and survivor benefits, or the Treasury Department’s contributions towards
military retirement, concurrent receipt, and the Medicare-Eligible Retiree Health Care fund.
Including more costs obviously increases the total cost of both AC and RC forces, and the way in
which these costs are apportioned to the active component and the reserve component can
significantly affect their comparative cost.66

How Should These Costs be Apportioned Between the Active and Reserve
Components?
Another challenge associated with determining comparative AC and RC costs revolve around
how to apportion certain costs. Certain costs can be apportioned to their respective component
more easily because they are provided through separate budgetary accounts. For example, the
active Army, Army Reserve, and Army National Guard each have their own appropriations for
personnel costs and for operations and maintenance costs. (Although even within these accounts,
there are some shared costs that are difficult to allocate.)67 Other costs are more difficult to
apportion. For example, procurement of major weapons systems and equipment for the reserve
components is done primarily via the active component account.68 A research and development
(R&D) account exists only for the active component, although the reserve component benefits
from it. Apportioning the costs from these accounts to the respective components poses
substantial challenges; but attributing all of the costs to the active component—particularly those
spent to purchase reserve component equipment—distorts the comparative cost of active and
reserve component forces.69 Additionally, the reserve component benefits from certain activities
conducted and funded largely by the active component—for example, developing doctrine,
building and operating bases, and running most military schools. Attributing these costs
exclusively to the active component likewise alters the comparative cost calculation. Finally,
some costs are difficult to apportion between the active and reserve components due to the lack of
research on the most appropriate way to do so. For example, if one wished to consider veterans’
benefits in the calculation of comparative active and reserve costs, one obstacle would be the
limited understanding of the extent to which active and reserve personnel use these benefits, a
problem compounded when one considers that many military personnel serve in both an active
and a reserve capacity during their careers.
66
For more information on how different counting methodologies affect total cost, see Eliminating Gaps in DOD Data
on the Fully-Burdened and Life-Cycle Cost of Military Personnel: Cost Elements Should be Mandated by Policy,
Washington, DC, January 7, 2013, http://ra.defense.gov/rfpb/_documents/
RFPB_Cost_Methodology_Final_Report_7Jan13.pdf. See pages 12-22, and Appendix B, Slides 16-17.
67
See comment later in the paragraph about activities funded by active accounts which are utilized by the RC. The
reverse is also true in some cases.
68
There is a reserve component procurement account known as the National Guard and Reserve Equipment Account
(NGREA), which is used for upgrading existing equipment and procuring new equipment; however, this account is
fairly small in comparison to the main active component procurement accounts.
69
Reserve component procurement funding can be identified through the NGREA account and the “Procurement
Programs (P1-R) Reserve Components” budget appendix document. However, this does not account for the costs of
equipment transferred (“cascaded”) from the active to the reserve components. Procurement costs are often ignored in
AC and RC cost comparisons, but this can be a critical variable, especially when using the Deployed Unit Cost
Approach. Under the Deployed Unit Cost Approach, multiple RC units may be needed to sustain the same output as
one AC unit. If this is the case, then the procurement costs associated with equipping multiple RC units can have a very
significant impact on comparative cost calculations.

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How Often Will Reserve Units Be Activated?
Another key factor in determining comparative AC/RC costs relates to the frequency with which
the RC unit is used. If RC units cost less than AC units when not activated, and about the same as
AC units when activated, then the comparative costs will vary based on how frequently the RC
unit is activated. Or, to put it another way, RC units will cost the least if they are never activated,
cost the same as AC units if they are continually activated, and fall somewhere in between based
on their ratio of active to inactive time. Thus, an RC unit that is activated for one year out of
every two years will be more expensive than one activated for one year out of every three years.
Likewise, an RC unit that is activated for one year out of every two years will be more expensive
than one activated for nine months out of every two years. These ratios, often referred to as
“deployment-to-dwell ratios,” became an increasingly important part of understanding RC costs
due to the large scale rotational deployment of RC units to Iraq and Afghanistan, and due to the
desire of many policy makers to continue using RC units for operational missions in the future.70
They also play an important role in determining the “boots on the ground” output metric
discussed below.

What is the Most Appropriate Way to Measure the “Output” of the Cost
“Inputs”?
A major change in how AC and RC costs are discussed today comes in the area of correlating the
“input” of cost (dollars) with various “outputs.” Perhaps the most common “output” used
historically in AC/RC cost comparisons has been personnel, as when Lieutenant General Jeffrey
Talley, Chief of the Army Reserve, noted that the Army Reserve provides “nearly 20% of the
Army’s trained Soldiers and units, for just six percent of the Army budget.”71 A somewhat
different formulation compares budget share and the number of personnel in each component,
resulting in a “cost per person” metric. For example, for FY2015 the Army has requested about
$120 billion in budget authority. Of this, about $98 billion is for active component accounts, and
$22 billion for reserve component accounts.72 The proposed end strength of active component
soldiers is 490,000, while the proposed end strength for reserve component soldiers is 552,200
(350,200 ARNG and 202,000 USAR).73 Using this approach, the cost per active soldier could be
70

See the new activation authority granted by the 2012 National Defense Authorization Act, codified at 10 USC
12304b, discussed in Appendix E.
71
Statement by Lieutenant General Jeffrey Talley before the U.S. Senate Armed Services Committee, April 8, 2014, p.
5, available at http://www.armed-services.senate.gov/download/talley_04-08-14pdf. Another example of this approach
was provided in a 2012 National Guard Bureau posture statement: “The National Guard currently provides 35-40% of
the Army and Air Force operational force for less than 7% of the base defense budget.... ” National Guard Bureau,
2012 National Guard Bureau Posture Statement, page 7, http://www.nationalguard.mil/portals/31/Documents/
PostureStatements/2012%20National%20Guard%20Bureau%20Posture%20Statement.pdf .
72
The total requested budget authority for the A

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/crs%3AR43808. Public record. Not legal advice.