Definitions for "Truman Doctrine"
(1947) - The dominant American foreign policy of the second half of the 20th Century, calling for U.S. aid to countries threatened by Communist revolution.
a policy enunciated in March, 1947, by President Harry Truman, when he pledged U.S. support for "free peoples who are resisting attempted subjugation by armed minorities or by outside pressures." If America failed to do this, said Truman, world peace would be endangered. The speech referred in particular to U.S. aid to Greece and Turkey.
a promise of US aid to all 'free peoples who are resisting attempted subjugation by armed minorities or by outside powers" (also see Brezhnev Doctrine)
committed the United States to protecting "free peoples" of Europe from attack.