Summary

Combating Terrorism: Need for Comprehensive Threat and Risk Assessments of Chemical and Biological Attacks
NSIAD-99-163  September 7, 1999

The ease or difficulty for terrorists to cause mass casualties with an improvised chemical or biological weapon depends on the agent selected. Experts agree that toxic chemicals can cause mass casualties and require little if any expertise or sophisticated methods. Most chemical nerve agents, however, are technically challenging for terrorists to acquire, manufacture, and produce. Also, terrorists working outside a state-run laboratory would have to overcome extraordinary challenges to effectively and successfully weaponize and deliver a biological agent and cause mass casualties. Although the intelligence community has issued assessments that discuss foreign-origin and biological terrorist threats, including judgements about which chemical and biological agents would most likely be used, the FBI has yet to produce a formal written assessment of the most likely domestic-origin chemical and biological terrorist threats. GAO believes that a sound national-level risk assessment could provide a strategic guide to help shape, focus, and prioritize federal efforts to combat terrorism. Such an assessment would be done by a multidisciplinary team of experts on intelligence, terrorism, chemical and biological agents, weapons, law enforcement, and health and other experts. The team could (1) generate valid threat scenarios, (2) assess and prioritize scenario risk in terms of the likelihood and the severity of consequences, and (3) determine appropriate countermeasures or other programmatic responses.

Subject Terms

Biological agents
Biological warfare
Chemical agents
Chemical warfare
Chemicals
Combating terrorism
Crime prevention
Domestic intelligence
Emergency preparedness
Homeland security
Risk assessment
Strategic planning
Terrorism
Terrorists