Homeland Defense:

DOD Needs to Assess the Structure of U.S. Forces for Domestic Military Missions

GAO-03-670: Published: Jul 11, 2003. Publicly Released: Aug 11, 2003.

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Davi M. Dagostino
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The way in which the federal government views the defense of the United States has dramatically changed since September 11, 2001. Consequently, the Department of Defense (DOD) has adjusted its strategic and operational focus to encompass not only traditional military concerns posed by hostile states overseas but also the asymmetric threats directed at our homeland by both terrorists and hostile states. GAO was asked to review DOD's domestic missions, including (1) how DOD's military and nonmilitary missions differ; (2) how DOD's military and nonmilitary missions have changed since September 11, 2001; (3) how the 1878 Posse Comitatus Act affects DOD's nonmilitary missions; and (4) the extent to which DOD's organizations, plans, and forces are adequate for domestic military missions and the consequent sustainability of the current mission approach.

DOD's military and nonmilitary missions differ in terms of roles, duration, acceptance, and capabilities normally employed. The threat of terrorism has altered some military operations. For example, as of September 11, 2001, the North American Aerospace Defense Command orders combat air patrols over U.S. cities to prevent terrorist attacks. The 1878 Posse Comitatus Act prohibits the direct use of federal military troops in domestic civilian law enforcement, except where authorized by the Constitution or acts of Congress. Congress has expressly authorized the use of the military in certain situations such as to assist with terrorist incidents involving weapons of mass destruction. DOD has established new organizations (such as U.S. Northern Command) and implemented a campaign plan for domestic military missions, but it has not evaluated or adjusted its force structure. GAO did not assess the adequacy of the new organizations or the campaign plan because the organizations were not yet fully operational, and the campaign plan was only recently completed. DOD's force structure is not well tailored to perform domestic military missions and may not be able to sustain the high pace of operations that preceded and followed the attacks on September 11, 2001. While on domestic military missions, combat units are unable to maintain proficiency because these missions provide less opportunity to practice the varied skills required for combat and consequently offer little training value. In addition, from September 2001 through December 2002, the number of servicemembers exceeding the established personnel tempo thresholds increased substantially, indicating that the present force structure may not be sufficient to address the increase in domestic and overseas military missions. As a result, U.S. forces could experience an unsustainable pace that could significantly erode their readiness to perform combat missions and impact future personnel retention.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: DOD partially concurred with GAO's recommendation. In the June 2005 DOD Strategy for Homeland Defense and Civil Support, DOD stated that it must equip and train warfighting forces, as necessary, for domestic Chemical, Biological, Radiological, Nuclear, and High Explosive (CBRNE) consequent management because civil authorities are likely to call upon DOD if this type of event occurs within the next 10 years. However, beyond an already dedicated command and control element designed for CBRNE, DOD will continue to rely on dual-capable forces for domestic consequence management. In the strategy, DOD stated that because DOD has limited resources and it needs to manage its risk, it decided to place its priority on being able to complete its homeland defense mission and that its civil support mission would be its second priority. In this regard, DOD has assessed the domestic military mission requirements and taken steps to only provide a dedicated command and control CBRNE element.

    Recommendation: The Secretary of Defense should assess domestic military mission requirements and determine if steps should be taken to structure U.S. forces to better accomplish domestic military missions while maintaining proficiency for overseas combat missions.

    Agency Affected: Department of Defense


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