Final answer:
The U.S. spent $13 billion on the Marshall Plan between 1948-1951, aiding European recovery post-World War II and countering communism.
Step-by-step explanation:
The United States spent $13 billion from 1948-1951 on the European Recovery Program, known as the Marshall Plan. This initiative was a vital component in the post-World War II rebuilding of European nations, and it played a crucial role in curbing the spread of communism by fostering economic stability and democracy in Europe. The funding for the Marshall Plan was deemed essential for reconstructing infrastructure, reviving industrial capacity, and preventing economic depression in the U.S., while also providing a bulwark against communist expansion during the early stages of the Cold War.