The first section provides an overview of NT, factors influencing the risks insurgent groups are willing to take in resorting to NT, and the implications for foreign policy. Terrorist access to a nuclear capability through access to existing weapons, weapon self-development, and sabotage of reactors is discussed. Factors contributing to an increased threat of NT are considered, including insensitivity to traditional deterrents, interterrorist cooperation, and tolerance and support of terrorism. Finally, the various forms of NT and their effects are described. The second section considers target hardening and behavioral strategies for preventing NT. Target hardening requires both improved physical security and nonproliferation. Behavioral strategies are proposed on the basis of a risk calculation for six types of terrorist groups characterized by their varying degrees of commitment and levels of criminality. Finally, factors influencing the effectiveness of international counterterrorism strategies are discussed. Chapter notes and index.