In what way would the rebuilding of european nations after world war ll stop the spread of communism?

Communism catered to very poor and destroyed countries. If we loaned the country money, that would boost their economy so they would fall to communism. One such case was the 1949 Marshall Plan, and it worked very well.

American leaders believed that, if nations and people had enough food & money, these European nations would not be susceptible to the promises of communists. America could also gain allies if they helped countries, and by doing so, American and Western ideologies would spread and fix themselves, so communism couldn't get a foothold.