The terrorist attacks of 11 September 2001 led to the largest US Government transformation since the formation of the Department of Defense following World War II. More than 22 different agencies, in whole or in part, and >170,000 employees were reorganized to form a new Cabinet-level Department of Homeland Security (DHS), with the primary mission to protect the American homeland. Legislation enacted in November 2002 transferred the entire Federal Emergency Management Agency and several Department of Health and Human Services (HHS) assets to DHS, including the Office of Emergency Response, and oversight for the National Disaster Medical System, Strategic National Stockpile, and Metropolitan Medical Response System. This created a potential separation of “health” and “medical” assets between the DHS and HHS. A subsequent presidential directive mandated the development of a National Incident Management System and an all-hazard National Response Plan.

While no Department of Veterans Affairs (VA) assets were targeted for transfer, the VA remains the largest integrated healthcare system in the nation with important support roles in homeland security that complement its primary mission to provide care to veterans. The Emergency Management Strategic Healthcare Group (EMSHG) within the VA's medical component, the Veteran Health Administration (VHA), is the executive agent for the VA's Fourth Mission, emergency management. In addition to providing comprehensive emergency management services to the VA, the EMSHG coordinates medical back-up to the Department of Defense, and assists the public via the National Disaster Medical System and the National Response Plan.

This article describes the VA's role in homeland security and disasters, and provides an overview of the ongoing organizational and operational changes introduced by the formation of the new DHS. Challenges and opportunities for public health are highlighted.