"This insight provides a brief overview of Stafford Act declarations under the Robert T. Stafford Disaster Relief and Emergency Assistance Act (hereinafter the Stafford Act--42 U.S.C. 5721 et seq.) and the types of assistance they could authorize in response to terrorist incidents. This report also provides examples of Stafford Act declarations that have been issued for previous terrorist attacks. [...] The Stafford Act authorizes the President to issue two types of declarations that could provide federal assistance to states and localities in response to a terrorist attack: a 'major disaster declaration' or an 'emergency declaration.' [...] Major disaster declarations authorize a wide range of federal assistance to states, local governments, tribal nations, individuals and households, and certain nonprofit organizations to recover from a catastrophic event. Major disaster declarations must be requested by the state governor or tribal leader. [...] Emergency declarations are issued by the President to protect property and public health and safety and to lessen or avert the threat of a major disaster. Emergency declarations can be issued before an incident when a threat is detected (for example, before a hurricane makes landfall) to supplement and coordinate local and state efforts such as evacuations and the protection of public assets."
CRS Insight, IN10507
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html