As fanatical or irrational as the new breed of terrorists may seem, like their more traditional counterparts, they have remained remarkably conservative operationally. For this reason, future terrorist use of chemical, biological, radiological, or nuclear (CBRN) weapons may be far less certain than is now commonly assumed. In the past, terrorism was practiced by a group of individuals belonging to an identifiable organization with a clear command and control apparatus who had a defined set of political, social, or economic objectives. Most significantly, these familiar terrorist groups engaged in highly selective and mostly discriminate acts of violence. These groups mostly comprised relatively small numbers of persons. In contrast, the new generation of terrorists shows several important organizational changes that in turn have affected their operations, decision making, and targeting. The absence of any existing, publicly identified central command authority is significant in that it may remove previous inhibitions on the terrorists’ desire to inflict widespread, indiscriminate casualties. Many terrorist movements today are also seen to have less easily defined aims or identified objectives. This array of changes has raised serious concern about the continued relevance of much of the conventional wisdom on terrorism – particularly as it pertains to potential future terrorist use of CBRN weapons. This new era of terrorism – supposedly more lethal and bloody than before – that the new terrorists were thought surely to wreak has yet to materialize. These trends do not necessarily imply that terrorists currently possess either the requisite scientific knowledge or technical capabilities to implement their violent ambitions. The lack of success of the Aum Shinrikyo group in their sarin gas attack in Japan is one example. The challenge in responding to the threat of terrorism is to craft a defense that is not only both cost effective and appropriate, but that is also sober and practical. 19 notes