The Monroe doctrine and Truman doctrine were similar as they both opposed the spread of communism as part of the United States foreign policy of containment. They were both designed to help the countries that were fighting communism. Truman Doctrine, for example, offered aid to all the nations that were fighting the spread of communism through the provision of economic and military support to countries such as Greece and Turkey to assist these countries from being communist. The Monroe doctrine, on the other hand, advocated that any attempt by a European power to control or oppress any Nation in the Western Hemisphere would be taken as a hostile act against the U.S.