The Truman Doctrine was an international-relations policy set
forth by the U.S. President Harry Truman in a speech on
March 12, 1947 stating that the U.S. would support Greece and Turkey with
economic and military aid to prevent their falling into the Soviet sphere this
made the cold war worse. Since Soviet Russia was Communist, they tried to
take over countries and we provided aid to the defending countries (except
China) which made Soviet Russia angry.