This diplomatic history of the Korean War examines the "police activity" whose effect on the Cold War has dominated international relations since 1945. While the major military decisions and events of the war are covered, Burton I. Kaufman focuses on the foreign policy decisions that directed U.S. involvement in Korea and that significantly defined America’s role as a world military-political power.

The subtitle outlines the three major areas of investigation. The first challenge was the atmosphere of crisis that pervaded Washington in the late 1940s and early 1950s. The Red Scare, McCarthyism, and the fear of Communist expansion abroad mobilized political and public sentiment in favor of military intervention. Then, in an effort to maintain its credibility at home and abroad, the Truman administration committed U.S. troops to a local conflict in a little-known country for almost three years.