Truman Doctrine

US president Harry Truman's 1947 dictum that the USA would ‘support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures’. It was used to justify sending a counter-insurgency military mission to Greece after World War II, and evolved into the policy of containment of Soviet expansion. See also United States of America, the Truman Doctrine.

In 1947 the UK was sending aid to Greece and Turkey, whose governments were threatened by communist expansion. When the UK announced that it could no longer afford to support these countries, Truman asked Congress to provide the means to resist communist takeovers. Congress responded with $400 million worth of military and economic aid, and the governments of Greece and Turkey prevailed.

The Truman Doctrine has been used to justify US action in Korea, Vietnam, and other areas outside US territory.