How did the Marshall Plan support the Truman Doctrine and the policy of containment?

The Marshall plan was to help build up Western European nations due to the fact that communism spreads easiest in poverty stricken war torn countries. Then to make it worst Europe is a collective of several countries that are closest to America’s borders from the Atlantic, so to further containing communism in the east, they had to solidify the Democracy in the west.

Imay be able to but what’s the question?