The fall of the Soviet Union in the early 1990s significantly changed the dominant 20th century notions of a ""balance of power"". Caught in a figurative tug-of-war between international co-operation on the one hand and unilateral military, political and economic dominance on the other, the United States struggled with its new, somewhat unfamiliar role as the world's lone superpower at century's end. The events of September 11, 2001 served to further polarize the political debate, with some emphasizing a multilateral diplomatic approach to fighting terrorism while others demanded immediate and widespread military action to preserve American interests and the world order. This book presents a clear and sophisticated argument that the United States is, and should continue to be, the world's guardian or sheriff, a metaphorical anchor in constantly shifting seas. This constructive critique of trends in national security is holistic, rooting defense issues and prospective answer both in the US national security policy, broadly defined and in the emerging international security environment. He sets forth a strategic analysis with nine basic themes as guides to where, when and how America should be involved in international security affairs. The book thus describes and prescribes America's continuing role as ""sheriff"" in an era marked by terrorism, political unrest and the increased interdependence of the world community.