With capitalist and communist regimes ensconced in Japan and China, respectively, Korean communists led by Kim Il Sung sought to "liberate" their peninsula through armed aggression. Archival evidence found in the 1990s revealed that Kim practically pleaded with Stalin, on numerous occasions, before gaining the Kremlin autocrat's assent to an attack against southern forces backed by the American-educated Syngman Rhee. The outbreak of war in Korea in June 1950 stunned the Truman administration and an American public already reeling from a series of Cold War setbacks. Unaware and unwilling to consider that Kim, and not Stalin, had fomented the war in Korea, the Truman administration decided immediately to respond with force to what it was sure was a deliberate Soviet provocation. Within months, U.S. and UN forces reversed the battle, prompting a massive Chinese intervention that turned the Korean War into a bloody three-year stalemate. Korea would remain a divided nation for at least the rest of the century, yet another casualty of the Cold War.
The outbreak of war in Korea, punctuated by the approval of the historic U.S. foreign policy document National Security Council Document 68 (NSC 68) marked the end of the first phase of the Cold War. The apocalyptic policy paper envisioned a fight to the finish with Soviet-sponsored world communism. The document, approved by Truman, literally envisioned spending whatever was necessary in the name of national security. During the course of the Korean War, defense spending more than tripled, ensuring the predominance of military Keynesianism for the remainder of the century. Military Keynesianism encompassed stimulation of the economy through federal investment and expenditure on defense.
Among other significant repercussions of the Korean bloodletting was the establishment of U.S. military bases in Asia; lasting involvement in the dispute between Taiwan and mainland China; assignment of U.S. troops to Europe on a permanent basis; and West German rearmament. Approval of NSC 68 culminated the first phase of the Cold War. The Korean War cemented militarization and the adoption of worst case scenarios of "enemy" behavior on both sides. Sometimes referred to as the "forgotten war," insofar as it was sandwiched between World War II and the Vietnam War, the Korean War was one of most significant conflicts in modern world history.