After Presidential Decision Directive 39 (PDD-39), issued in June 1995 (see June 21, 1995), requires key federal agencies to maintain well-exercised counterterrorist capabilities, the number of counterterrorism exercises being conducted increases significantly. According to a 1999 report by the General Accounting Office, whereas 32 counterterrorist exercises are held between June 1995 and June 1996, from June 1997 to June 1998, 116 such exercises are conducted. Some of the exercises held between June 1995 and June 1998 are “tabletop exercises,” where participants work through a scenario around a table or in a classroom and discuss how their agency might react; others are “field exercises,” where an agency’s leadership and operational units practice their skills in a realistic field setting. Four exercises during this period are “no-notice” exercises, where participants have no advance notice of the exercise. These four exercises are conducted by either the Department of Defense (DoD) or the Department of Energy. DoD leads 97 of the exercises—almost half of the total—held between June 1995 and June 1998. The Secret Service leads 46, the FBI 24, and the Federal Emergency Management Agency (FEMA) leads 16. Most of the exercises are conducted in the US and are based around the scenario of a domestic terrorist attack. Although intelligence agencies have determined that conventional explosives and firearms continue to be the weapons of choice for terrorists, the majority of exercises are based around scenarios involving weapons of mass destruction (WMD)—chemical, biological, or nuclear weapons or agents. More than two-thirds of the exercises have WMD scenarios, with the most common WMD being chemical agents, such as sarin. The other exercises have more traditional and more likely scenarios involving conventional weapons and explosives. [United States General Accounting Office, 6/25/1999 ; Washington Post, 10/2/2001
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