CIAO DATE: 07/02

Defending America: Redefining the Conceptual Borders of Homeland Defense
The Risks and Effects of Indirect, Covert, Terrorist, and Extremist Attacks with Weapons of Mass Destruction
Challenges for Defense and Response

Anthony H. Cordesman, Arleigh A. Burke Chair for
Strategy Center for Strategic and International Studies

The Center for Strategic and International Studies

February 2001

From a public policy viewpoint, these uncertainties mean the US must prepare for a wide variety of low probability attacks on the US, rather than to emphasize any given form of attack or group of attackers. The US must plan its Homeland defense policies and programs for a future in which there is no way to predict the weapon that will be used or the method chosen to deliver a weapon which can range from a small suicide attack by an American citizen to the covert delivery of a nuclear weapon by a foreign state. There is no reason the US should assume that some convenient Gaussian curve or standard deviation, will make small or medium level attacks a higher priority over time than more lethal forms.

The US government is still deciding how to come to grips with these problems and how to assess possible methods of attack. A GAO report that summarized CIA and FBI views on these issues reached the following conclusions, although it must be stressed that the analysis focused on the normal historical pattern of actions by terrorists/extremists, and largely excluded attacks by state actors, proxy attacks, or covert attacks: ₁

The possibility that terrorists may use chemical or biological materials may increase over the next decade, according to intelligence agencies. According to the Central Intelligence Agency (CIA), interest among non- state actors, including terrorists, in biological and chemical materials is real and growing and the number of potential perpetrators is increasing. The CIA also noted that many such groups have international networks and do not need to be tied to state sponsors for financial and technical support. Nonetheless, the CIA continues to believe that terrorists are less likely to use chemical and biological weapons than conventional explosives. We previously reported that according to intelligence agencies, terrorists are less likely to use chemical and biological weapons than conventional explosives, at least partly because chemical and biological agents are difficult to weaponize and the results are unpredictable.

...The CIA classified the specific agents identified in intelligence assessments that would more likely be used by foreign- origin terrorists. The CIA also classified the intelligence judgments about the chances that state actors with successful chemical and/ or biological warfare programs would share their weapons and materials with terrorists or terrorist groups. Unlike the foreign- origin threat, the FBI's analysts' judgments concerning the more likely chemical and biological agents that may be used by domestic- origin terrorists have not been captured in a formal assessment. However, FBI officials shared their analyses of the more likely biological and chemical threat agents on the basis of substances used or threatened in actual cases.

In analyzing domestic-origin threats, FBI officials grouped chemical and biological agents and did not specify individual agents as threats. Although the FBI has not addressed the specific types of chemical or biological weapons that may be used by domestic terrorists in the next 2 to 5 years, FBI officials believe that domestic terrorists would be more likely to use or threaten to use biological agents than chemical agents.

The FBI's observation is based on an increase in reported investigations involving the use of biological materials. In 1997, of the 74 criminal investigations related to weapons of mass destruction, 30 percent (22) were related to the use of biological materials. In 1998, there were 181 criminal investigations related to weapons of mass destruction, and 62 percent (112) were related to the use of biological materials. Most of these investigations involved threats or hoaxes. The FBI estimated that in 1997 and 1998, approximately 60 percent of biological investigations were related to anthrax hoaxes.

The FBI ranks groups of chemical and biological agents on its threat spectrum according to the likelihood that they would be used.

• Biological toxins: any toxic substance of natural origin produced by an animal or plant. An example of a toxin is ricin, a poisonous protein extracted from the castor bean.
• Toxic industrial chemicals: chemicals developed or manufactured for use in industrial operations such as manufacturing solvents, pesticides, and dyes. These chemicals are not primarily manufactured for the purpose of producing human casualties. Chlorine, phosgene, and hydrogen cyanide are industrial chemicals that have also been used as chemical warfare agents.
• Biological pathogens: any organism (usually living) such as a bacteria or virus capable of causing serious disease or death. Anthrax is an example of a bacterial pathogen.
• Chemical agents: a chemical substance that is intended for use in military operations to kill, seriously injure, or incapacitate people. The FBI excludes from consideration riot control agents and smoke and flame materials. Two examples of chemical agents are Sarin (nerve agent) and mustard gas (blister agent).

Full Text (PDF, 531 pages, 174K)

Endnotes

Note 1: GAO/NSIAD-99-163, Combating Terrorism: Need for Comprehensive Threat and Risk Assessments of Chemical and Biological Attacks," pp. 18-17Back