How has the course of the US foreign policy changed in comparison with the pre-war time?

Before the war, the United States tried not to get involved in the politics of European countries, limiting itself to achieving its interests in the American continents.

After the war, the United States begins to actively participate in all world processes, offering economic or military assistance to countries in need. The United States is initiating the creation of a NATO bloc, which was designed to neutralize a possible threat from the USSR and its allies.

In addition, the United States is pursuing an active foreign policy in relation to other countries, striving to become the hegemon in the world and prevent the strengthening of the USSR.