Truman Doctrine

President Harry Truman's 1947 pledge to support free peoples resisting armed minorities or outside pressure, starting with aid to Greece and Turkey.

Containment: The Cold War strategy of blocking Soviet expansion through counterpressure rather than direct war. The doctrine turned containment from a strategic argument into declared American policy.
Marshall Plan: The 1948–1952 US economic aid program that rebuilt Western European economies, distributing about $13 billion in grants. The economic counterpart that translated the doctrine's pledge into large-scale funding.
Appeasement: The 1930s policy of conceding to aggressive powers to avoid war, discredited after the Munich Agreement. Truman and Acheson invoked its failure to justify confronting the Soviet Union immediately.
Greek Civil War: The 1946–1949 conflict between the Greek government and communist insurgents, ended with British and American support. The doctrine's first case: $300 million in American aid helped defeat the insurgency.
Truman's March 12, 1947 address: Truman's message to Congress requesting $400 million for Greece and Turkey and pledging support for free peoples. The speech itself is the mechanism: one sentence turned a regional crisis into a global pledge.
George F. Kennan: American diplomat and strategist whose 1946 Long Telegram and 1947 'X' article framed Soviet containment. His analysis supplied the intellectual case, though he thought the doctrine was too sweeping.
NATO: The 1949 military alliance binding the United States to the defense of Western Europe against Soviet attack. The doctrine's open-ended commitment deepened into a formal mutual-defense treaty.
Wallace's 1946 Madison Square Garden speech: Commerce Secretary Henry Wallace's 1946 call for cooperation with the Soviet Union, which got him dismissed. The leading domestic alternative: negotiation with Moscow instead of confrontation.
Turkish Straits crisis: Soviet pressure on Turkey in 1946 for control of the Dardanelles and joint defense of the straits. The second target of the doctrine: American naval signaling backed Turkey's refusal.
Economic Cooperation Administration: The US agency created in 1948 to administer Marshall Plan aid to Europe. The administrative machinery later used to deliver aid under the doctrine's umbrella.

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