9/11 and the Army Reserve: The Strategic Shift

August 31, 2021 | Colonel Matthew W. Lawrence

Military members stand waiting for the the 2019 Pentagon September 11 Observance to begin at the Pentagon 9/11 Memorial in Arlington, Va., Sept. 11, 2019. President of the United States, Hon. Donald J. Trump, Chairman of the Joint Chiefs of Staff, Gen. Joseph F. Dunford, Jr., and Secretary of Defense, Hon. Mark T. Esper, hosted the ceremony. (U.S. Army photo by Sgt. Dana Clarke)

The 9/11 attacks’ effects on the United States and its foreign policies cannot be understated. The United States, in essence, lost its innocence that day and has never been the same. The attacks spurred changes in the way the United States handles national security, secures air transportation, and shares intelligence. The attacks also resulted in, directly and indirectly, two major armed conflicts that lasted the next two decades. These conflicts served as the catalyst for the most significant strategic shift in the US Army Reserve’s history—the organization’s transformation from a strategic force to an operational one. This transformation was not merely policy; it was ingrained in the organizational spirit as well.

The Army Reserve has long struggled to be a major element of the national security picture. The smallest of the three Army components (the active force, Army National Guard, and Army Reserve), the Army Reserve had been used sparingly since World War II—or, in the case of the Vietnam War, hardly at all. Its existence throughout the Cold War as a strategic reserve led to a force that was significantly less well equipped and well trained than the active force.1 Despite the lofty goals of the 1973 Total Force Policy, which was supposed to integrate reserve components into all Army missions more effectively, the Army Reserve remained a strategic force that was only to be used if the nation found itself in large-scale conflicts.2

Incremental improvements to the reserve components occurred before the 9/11 attacks, but progress remained slow. Even after the lessons learned in Operation Desert Shield and Operation Desert Storm, in which nearly 35,000 Army Reserve soldiers deployed to southwest Asia, the Army Reserve remained a strategic reserve (21,000 of these mobilizations were individual fills for active units from the Individual Ready Reserve).3 Its equipment was older than and often incompatible with the active force’s equipment, training funds were limited, and the expectation was reserve units would take months to deploy and could not be relied upon for immediate needs.

The term “operational reserve” began to gain footing after Operation Desert Storm.4 The concept, defined slightly differently by each component and the DoD, was the reserve components needed to be manned, equipped, and trained to support adequately the full spectrum of the Army’s operational requirements. Realizing this vision would not be an insignificant task. The Army Reserve had long been at the end of the pecking order for resources, despite Army and congressional programs (for example, Bold Shift and the National Guard and Reserve Equipment Account) that were designed to improve the readiness of the reserve components. The improvements were incremental. Army Reserve units were never funded to train fully to proficiency, and, despite on-hand equipment gains, much of their equipment was outdated and required expensive retrofitting or replacement to remain relevant. In addition, spending cuts in the drawdown years between Operation Desert Storm and the 9/11 attacks stymied these programs and blunted every improvement.

The root of the Army Reserve’s strategic pivot were the September 11 attacks. The attacks on the United States changed both how the Army used the Army Reserve and, more importantly, how the Army Reserve perceived itself. The term “operational reserve” immediately gained an importance it had previously lacked. Over the next 20 years, over 420,000 Army Reserve soldiers would mobilize and deploy, more than in all of the conflicts since the Korean War combined.6

The differences in the performance of the Army Reserve were immediately apparent. Directly following the attacks, a wave of hasty mobilizations across the country placed Army Reserve soldiers and units in key homeland defense roles within three days. Half of the units mobilized in response were trained and deployed in less than 15 days, much quicker than the historical average.7 By the start of hostilities in Afghanistan in 2002, the Army Reserve had deployed public affairs, psychological operations, and numerous medical units alongside the active forces deployed there.8 The Army Reserve would struggle through the next five years to keep up with its requirements. Mobilizing units routinely required an influx of a large percentage of personnel from other units to be fully manned, and equipment shortfalls were solved by a system in which incoming Army Reserve units would fall in on the equipment of the unit they were replacing.

The Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005 officially recognized the need for the operational capabilities of the reserve components and established the Commission on the National Guard and Reserves.9 This committee concluded the reserve components provided critical capabilities for the United States’ national defense and should be resourced to contribute to all of the nation’s military missions. Many recommendations from the commission were finally mandated in 2008 by Secretary of Defense Robert Gates in DoD Directive 1200.17, Managing the Reserve Components as an Operational Force.10

This directive represented the realization of everything the Army Reserve had strove for since the establishment of the Total Force Policy 35 years prior. The directive directed the continued integration of reserve and active forces in all missions as well as major improvements to benefits and support programs accessible to reserve component soldiers. Reserve soldiers gained access to TRICARE, the Army’s medical insurance program, and numerous other soldier and family support programs previously unavailable to them. Acquisition policies prioritized equipping the reserve components alongside the active force, not as an afterthought. Additional funding followed the directive—and, with it, much-needed additional training, which had before depended on Overseas Contingency Operations funds. The Army Reserve could afford to train in time to prepare properly for its continued deployments.

Most significantly, the 9/11 attacks and the events that resulted from them changed the mindset of soldiers. Before, deployments were uncommon and, for some specialties, simply did not happen. Now, Army Reserve soldiers could expect to deploy. Combat patches, which had most often been found on the sleeves of former active-duty soldiers from Operation Desert Storm, became the norm. Frequent deployments meant soldiers in the force were getting valuable practice doing their wartime jobs and had more experience working directly with active-duty troops. The risks of deployment also became real, with over 2,000 Army Reserve soldiers either killed or wounded over the next two decades.11 Training quickly took on a seriousness and urgency it previously had not.

These events represented the high watermark of the Army Reserve since its creation as a small group of medical professionals in 1908. Despite the challenges it faced, the Army Reserve fulfilled every one of its deployment requirements. Motivation was high, as were the Army’s expectations. The Army Reserve fielded new equipment and technologies, created new partnerships with the active forces, and played its part as the Total Force Policy had originally intended. But as the armed conflict in the Middle East has subsided, so has the funding for these initiatives and the Army Reserve’s readiness.

The challenge the Army Reserve faces now is collectively maintaining its operational mindset. The United States’ global conflicts have diminished, and significantly fewer Army Reserve soldiers are currently deployed overseas. Combat patches are less common as veterans of Afghanistan and Iraq age leave the force; their junior replacements lack the opportunity to earn one. Recent programs highlight the diminished funding for an operational reserve. The Army Reserve’s most recent readiness initiative prioritizes only one-third of its units as operational.12

The Army Reserve continues to support key elements of the United States’ military power. Key capabilities such as civil affairs and psychological operations are mostly found in the Army Reserve, as are the majority of the Army’s medical, logistical, and legal units. Over 5,000 medical and logistics soldiers deployed nationwide in response to the coronavirus pandemic; 16,000 Army Reserve soldiers remain deployed worldwide, its forces assist the Department of State with yearly international, soft-power missions, and it has responded to assist in hurricane recovery efforts numerous times.13 The opportunity and the resources that made the operational Army Reserve possible may have dwindled, but the spirit is still there. As the Army Reserve enters what most hope will be the post-COVID era with limited international deployments, maintaining the intensity, duration, and realism in training that enabled the force to be the relevant and ready organization it had aspired to be will be its major strategic challenge.

  1. Carl L. White, The Army National Guard and Army Reserve: An Operational Transformation (Carlisle, PA: US Army War College Press, April 13, 2010).
  2. Alice Buchalter and Seth Elan, Historical Attempts to Reorganize the Reserve Components (Washington, DC: Library of Congress, October 2, 2007).
  3. Kathryn Roe Coker, The Indispensable Force: The Post-Cold War Operational Army Reserve, 1990–2010 (Fort Bragg, NC: Office of Army Reserve History, 2013).
  4. Coker, Indispensable Force.
  5. White, Army National Guard; and Coker, Indispensable Force.
  6. Elmer Mason, “USAR Historical Mobilization Data 2007–2021” (PowerPoint presentation, US Army Reserve Command, Fort Bragg, NC, June 22, 2021); Michael Sheffield, e-mail message to the author, August 9, 2021; and “The History of the Army Reserve,” US Army Reserve, March 31, 2014, Infographic%20Final.pdf.
  7. Thomas F. Lippiatt et al., Mobilization and Train-Up Times for Army Reserve Component Support Units (Santa Monica, CA: RAND Corporation, 1992).
  8. Coker, Indispensable Force.
  9. Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005, Pub. L. No. 108-375, 27 Stat. 445 (2004).
  10. Robert M. Gates, Managing the Reserve Components as an Operational Force, DoD Directive 1200.17 (Washington, DC: Office of the Secretary of Defense, October 29, 2008).
  11. Coker, Indispensable Force.
  12. Debra Richardson, “Designated Army Reserve Ready Force X Units Set to Shape Future Battlefields,” Defense Visual Information Distribution Service, March 25, 2018,
  13. “Lt. Gen. Jody J. Daniels, Chief of Army Reserve and Commanding General, US Army Reserve Command – Message to the Force,” US Army Reserve, n.d.,; Jordan Amman, “3rd Medical Command and the Jordanian Royal Medical Services Exchange Lessons on COVID-19,” Defense Visual Information Distribution Service, October 22, 2020,; and “America’s Army Reserve Relief Support for Hurricane Maria,” Defense Visual Information Distribution Service, n.d.,

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