Introduces major concepts, debates and challenges in international security policy. Some of today's problems have existed in various forms for centuries, such as potential conflicts between great powers, violence by governments against their own people and by terrorist organizations, and the disruptive effects of powerful new technology. Some are more recent, such as nuclear deterrence and nonproliferation, humanitarian crises and human security. And others, including cyber security, drones and climate change, are the leading edge of future security challenges. Fundamental questions about how to make the world safer will be a major theme of this course.