The Truman Doctrine was a policy set forth by President Harry S. Truman
in a speech delivered on March 12, 1947 stating that the U.S. would support
Greece and Turkey with financial and military air to prevent their falling to
communism, which would have had grave consequences thought the region.

The policy won the support of Republicans who controlled Congress and
involved sending $400 million, but no military forces, to the region

.