Answer: Reminiscent of the much earlier Monroe Doctrine, which stated that those countries that had won their independence from their colonizers could not be recolonized, the Truman Doctrine (1947) stated that the U.S. would support Greece and Turkey both economically and militarily in order to prevent their annexation by the USSR. This was in an effort to support his ideas of containment. In other words, to limit and prevent the expansion of communism and soviet ideologies. Due to their proximity to the USSR Greece and Turkey were at great risk of falling under soviet control. The Truman Doctrine resembled the Monroe doctrine in that it supported the sovereignty of other nations in order to protect America's .