facilities for the intensive supportive care that they would need to achieve long-term survival when they eventually became ill with acute radiation syndrome (ARS) during the following days and weeks.

Terrorist groups have indicated an interest in using weapons of mass destruction (WMDs), including nuclear weapons, against the United States, although there is no evidence to date to confirm that any particular group possesses nuclear weapons. Considering the inherent difficulties, it is not known whether such a group actually could develop the capacity to carry out such an attack in the near future, and there is a range of views among experts on the extent of the threat (Levi, 2007; Commission on the Prevention of Weapons of Mass Destruction Proliferation and Terrorism, 2008). Gaining access to sufficient quantities of weapons-grade nuclear material is the highest hurdle facing would-be nuclear terrorists, and numerous other hurdles would have to be overcome before a weapon devised from such material could be used. For example, terrorist groups would require the capacity to manufacture a device that would detonate when (and only when) they wanted. They also would have to transport the device into or within the United States and move it to the targeted location without being detected.

The United States has made preventing such an attack a high priority and has a number of programs in place to (1) deny terrorists access to nuclear materials, (2) deter other nations from helping terrorists mount a nuclear attack, and (3) intercept any attack before it can succeed. Still, since no individual preventive measure or even a set of such measures is fail-proof, the question remains: What if prevention efforts fail?

Over the past several years, the U.S. government has made increased efforts to address this question. In 2004-2005, the Department of Homeland Security (DHS) drafted 15 scenarios to be used in conjunction with planning responses to catastrophic events under the National Response Framework (NRF). The scenarios were chosen to “highlight a plausible range of major events such as terrorist attacks, major disasters, and other emergencies, that pose the greatest risk to the Nation.”¹ Relevant to the current discussion, Scenario 1 involves the detonation of a 10-kt IND in the central business district of a large city. The NRF also has a Nuclear/Radiological Incident Annex describing the “policies, situations, concepts of operations, and responsibilities of the Federal departments and agencies governing the