This course examines the origins and evolution of modern terrorism, challenges posed by terrorist groups to states and to the international system, and strategies employed to confront and combat terrorism. We assess a wide variety of terrorist organizations, and explore the psychological, socioeconomic, political, and religious causes of terrorist violence past and present. We also analyze the strengths and weaknesses of various counterterrorism strategies, from the point of view of efficacy as well as ethics, and look into ways in which the new threat of global terrorism might impact the healthy functioning of democratic states. The course is divided into two parts. Part I focuses on the terrorist threat, including the nature, roots, objectives, tactics, and organization of terrorism and terrorist groups. Part II addresses the issue of counterterrorism, including recent American efforts to combat terrorism, the strengths and weaknesses of counterterrorist tools and instruments, the issue of civil liberties and democratic values in confronting terrorism, and international strategies and tactics.