In the past, national security has centered on the strategies that political and military leaders pursue in their respective countries to defend their national interests, with a focus on military, diplomatic, economic, and informational instruments of power. In recent decades, however, the world has become more interdependent and the number and character of the threats have become, respectively, more numerous and complex, with some threats crossing national boundaries and challenging the well being of humanity as a whole. Thus, the current list of immediate and long-term threats to the national interests of the United States and other countries now includes interstate conflicts, civil wars marked by genocide, abuses of human rights, attacks on civilian populations by terrorist organizations, the proliferation of weapons of mass destruction, global pandemics, and the catastrophic effects of global climate change. In response to these developments, a new perspective to security has recently emerged, one that prioritizes “human security.” In 1994, the United Nations Development Report adopted this approach as its central organizing theme, arguing that the traditional notion of security was too narrow because it ignored the degree to which ordinary people felt threatened by crime, hunger, disease, and environmental hazards. While the traditional notion of security remains of central importance, the Clarke Forum embraces the broader concept of “human security” as the proper organizing principle of its 2011-12 theme: Security Challenges of the 21st Century.