The author’s 1998 white paper (completed for the US Department of Defense as a result of Presidential Decision Directive 39) applied the research literature on behavioral and organizational response to outline what might occur in the aftermath of a terrorist attack. It argued that it presented the best model available and should be applied when developing mitigation, preparedness, and response plans in anticipation of possible domestic nuclear, biological, and chemical terrorism.The terrorism events of September 11, 2001, have provided a basis for assessing this argument. The current article reviews the earlier argument by using updated disaster research to describe the behavioral and organizational response challenges a community or nation would likely encounter in a terrorist attack with weapons of mass destruction (WMD). Anecdotal evidence from the events of 9/11 is included to assess the efficacy of the literature as a model.