Before the terrorist assaults of September 11 and the anthrax letter attacks that followed, U.S. officials often drew a distinction between the threat posed by national chemical and biological weapons programs and the threat posed by terrorists using chemical and biological weapons. The two threats were seen as separate problems, requiring separate solutions. In the intervening months, however, it has become clear that the two proliferation problems are closely linked, in that assistance from national programs is likely to be critical to terrorist efforts to acquire and use chemical or biological weapons successfully, particularly on a large scale. This underscores the urgency of pursuing nonproliferation measures that delegitimize such weapons and complicate the efforts of both nations and terrorist organizations to acquire them.
