Justin Magula is a U.S. Army Strategist at the U.S. Army War College. He is on Twitter @JustinMagula. The views contained in this article are the author’s alone and do not represent those of the U.S. Army War College, the Department of Defense, or the United States Government. Divergent Options’ content does not contain information of an official nature nor does the content represent the official position of any government, any organization, or any group.

National Security Situation:  Of the United States Army’s four strategic roles in support of the Joint Force, prevailing in large-scale ground combat is the most important[1]. The Army cannot accomplish this strategic role without an appropriately designed operational headquarters.

Date Originally Written:  March 4, 2021.

Date Originally Published:  April 5, 2021.

Author and / or Article Point of View:  The author believes that operational and strategic headquarters play a significant role in the Army’s ability to achieve success in large-scale combat operations and that the Army underinvests in these capabilities.

Background:  In the past seven decades, the United States Army has reduced the number of operational-level headquarters it employs as part of its total force reductions[2]. The United States Army currently uses theater armies, corps, and divisions in roles that often exceed their designated functions. While this method has achieved some success in fighting irregular wars, it would likely prove less successful against a peer competitor.

Theater armies fulfill five persistent tasks in support of geographic combatant commands: set conditions in a theater for the employment of landpower, support theater security cooperation, provide support to other services, maintain administrative control of all Army forces in the theater, and provide operational control and sustainment support of any assigned or attached forces. Even though a theater army performs an impressive array of tasks, it is not designed to command and control units in combat. Alternately, U.S. Army corps serve as the Army’s highest tactical echelon in large-scale ground combat operations, overseeing combat divisions and subordinate units. Where theater armies focus across an entire theater, corps focus on designated areas of responsibility.

Significance:  The possibility of large-scale combat operations against Russia and China continues to increase[4]. A war against either country would likely require the Army to deploy a sizable land force. For such operations, the Army would require more than one corps and operational-level headquarters to oversee tactical operations. Currently, the Army does not have a headquarters designed to effectively command and control multiple corps in large-scale ground combat or serve as a land component command in a joint operational area in the event of a great power war[5].

Historically, the U.S. Army used field armies to control multiple corps and subordinate units in large-scale combat operations, like in both World Wars and the Korean War. The U.S. Army no longer has such a headquarters. Creating new field armies would give the army the ability to quickly transition to combat operations and control multiple corps if required.

This option paper proposes two possible solutions to fill this critical headquarters gap: forward-stationed field armies or expeditionary field armies.

Option #1:  The U.S. Army establishes forward-stationed field armies.

In this option, the U.S. Army would create field armies and forward station them in specific theaters. For instance, the Army could station a field army in the Indo-Pacific region as a subordinate headquarters to U.S. Army Pacific and one in Europe to support U.S. Army Europe and Africa since these are the two most likely theaters where large-scale combat operations would occur.

Risk:  Placing field armies forward in a theater would increase their vulnerability as prime targets for enemy attacks in war. These units would have difficulty transferring to support other theaters if the need arose. The cost of new facilities, equipment, and personnel would be high and would rely on host nation contract support.

Gain:  Creating forward stationed field armies allows the theater armies, as the field armies’ higher headquarters, to focus their efforts across the entire theater during competition and conflict as they are designed to do[6]. Additionally, these field armies could conduct theater-specific exercises, integrate with partner nations forces, and provide training oversight for subordinate units during competition. If the need arose to transition to combat operations quickly, these headquarters would be trained, ready, and integrated across their respective theaters.

Option #2:  The U.S. Army establishes expeditionary field armies.

The Army could create expeditionary field armies and base them in the United States. These field armies would be the same size as the forward-stationed ones. Like its current divisions and corps, the Army could use these field armies in an expeditionary manner to support American objectives abroad.

Risk: Under this option, these field armies would not have the same level of understanding of a specific theater as a forward-stationed unit might or the same level of integration with other theater forces and partners. In crisis, these field armies could deploy directly to a combat zone. In peacetime, these headquarters could risk being stretched thin by global commitments, exercises, and training oversight if placed in charge of other stateside Army units.

Gain:  This option would give the Army the greatest versatility to respond to almost any combat mission. Each expeditionary field army could be deployed in a tailored package to meet the theater commander’s needs, thus reducing the burdens of the theater army staff. The field armies could provide training oversight of other Army units in the United States, enabling better large-scale combat training for them. The field armies could also assist U.S. Army North for homeland defense and Defense Security Cooperation Agency missions. This structure would also provide the greatest employment opportunities for American civilians supporting these headquarters.

Other Comments:  None.

Recommendation:  None.


[1] U.S. Department of the Army, Army Doctrine Publication (ADP) 1, The Army. (Washington, DC: Government Printing Office, 2019), v.

[2] Bonin, J. and Magula, J. (2021). U.S. Army Europe and Africa Headquarters: Reforming for Future Success. War on the Rocks. Retrieved March 3,2021 from https://warontherocks.com/2021/02/u-s-army-europe-and-africa-headquarters-reforming-for-future-success/

[3] Lundy, M. (2018). “Meeting the Challenge of Large-Scale Combat Operations Today and Tomorrow.” Military Review. Retrieved March 3, 2021 from https://www.armyupress.army.mil/Journals/Military-Review/English-Edition-Archives/September-October-2018/Lundy-LSCO/

 [4] U.S. Army Training and Doctrine Command. (2018). “U.S. Army Concept: Multi-Domain Combined Arms Operations at Echelons Above Brigade 2025-2045.” TRADOC Pamphlet 525-3-8. Retrieved March 3, 2021 from https://adminpubs.tradoc.army.mil/pamphlets/TP525-3-8.pdf

[5] U.S. Joint Chiefs of Staff, Joint Publication (JP) 3-31, Joint Land Operations.  (Washington, DC: Government Printing Office, 2019), I-11.

[6] U.S. Department of the Army, Field Manual (FM) 3-94, Theater Army, Corps, and Division Operations. (Washington, DC: Government Printing Office, 2014), 2-4.