This paper draws together several years of work in an attempt to suggest the outlines of this thinking about the risk that I regard as most pernicious: biological terrorism. It is written for those who desire a better understanding of this risk and its implications for policymakers. Section I delineates the problem that confronts us. It describes the character and magnitude of the risk of biological terrorism and identifies the factors that differentiate bioterrorism from other modes of terrorism. This section also comments on why biological terrorism has not yet emerged as an important...

The terrorist attacks of September 11, 2001, brought together two related but distinct phenomena. First, they presented the calling card of al Qaeda and more generally of militant Islam. These attacks were rightly perceived as an act of war by a group seeking to catalyze a political-religious movement. Much of America's effort since then has been to destroy that group, its sanctuaries, and its affiliates; some of the effort has been to counter the psychological, social, and political appeal of militant (predominantly Wahabi) Islam. Second, these attacks introduced the public to a more general...