The new defense challenge confronting the United States involves a range of nontraditional warfare threats that are far different from the large-scale conventional or nuclear threats posed by the Soviet Union during the Cold War. Now at the forefront, threats involving chemical, biological, and nuclear weapons from secondary states and terrorist groups along with other ill-defined forms of nontraditional warfare-urban, information, drug, terrorist, and guerrilla-undermine the effectiveness of the modern U.S. military and other government agencies. This volume brings together the wide-ranging talent of technologists, academics, and journalists to define the nature of these nontraditional threats and the potential means to counter them. They point out shortcomings in U.S. policy as well as organizational shortfalls that must be corrected in order to better prepare the means to meet and defeat these unusual and ill-defined threats.