The late 1940s marked the origin of what the journalist and political philosopher Walter Lippmann called, in 1947, the Cold War, denoting the emerging confrontation between the United States and the Soviet Union. The term remained in use as a shorthand description of Soviet-American relations and an explanation of most of American foreign policy until 1989 or 1990. World War II ended in the summer of 1945, and the Korean War began in the summer of 1950. The United States and the Soviet Union spent much of the intervening five years defining their postwar relationship. Each nation pursued its vision of world order, exploring the possibilities of cooperation in achieving its goals, and testing the limits of the other's tolerance in pursuit of unshared goals. Each exploited the extraordinary opportunity to extend its influence in the vacuum created by the defeat of Germany and Japan and the decline of British power.