If this is for an essay, you might want to read about Thomas Hobbes and the state of nature. He makes pretty bold claims about why human beings fight one another. Watch a video on it.
Hello,
The Western Allies developed industries in Germany because the Marshall plan was only for countries following the American Economic model. They also held on tightly to Berlin. In fact--Western Berlin was controlled by Allies which supplied food and other essential goods.
The majority of American intervention in the foreign affairs occurred during the Cold War (this is your answer). Latin America was a frequent hotspot for activity as well especially towards the latter half of the Cold War with Fidel Castro's rise to power in Cuba.