Cold War Domino Theory
The United States feared Vietnam would trigger a regional communist takeover. President Eisenhower first voiced this concern in 1954, comparing Southeast Asian nations to a row of dominoes. If Vietnam fell, officials believed Laos, Cambodia, and Thailand would quickly follow suit. American foreign policy experts used this theory to justify increasing involvement, though many historians now question whether such a chain reaction was likely. The concept nonetheless shaped decades of strategic thinking about the region.
