Containment policy

Containment is a geopolitical strategy to stop the expansion of an enemy. It is best known as a Cold War foreign policy of the United States and its allies to prevent the spread of communism. As a component of the Cold War, this policy was a response to a series of moves by the Soviet Union to increase communist influence in Eastern Europe, China, Korea, Africa, and Vietnam. Containment represented a middle-ground position between detente and rollback.

The basis of the doctrine was articulated in a 1946 cable by U.S. diplomat George F. Kennan during the post-World War II administration of U.S. President Harry S. Truman. As a description of U.S. foreign policy, the word originated in a report Kennan submitted to U.S. Defense Secretary James Forrestal in 1947. It was a report that was later used in a magazine article. It is a translation of the French cordon sanitaire, used to describe Western policy toward the Soviet Union in the 1920s.

Although the term "containment" was first used for the strategy in the 1940s, there were major historical precedents familiar to Americans and Europeans. In the 1850s anti-slavery forces in the United States developed a containment strategy (they did not use the word) for stopping the expansion of slavery and forcing its collapse. Historian James Oakes explains the strategy:

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