In terms of world involved after World War ll how did the US change its policy?

After World War II, the United States shifted its foreign policy from isolationism to a more interventionist approach, emphasizing containment of communism. The establishment of NATO in 1949 and participation in conflicts like the Korean War illustrated its commitment to collective security and global involvement. Additionally, the U.S. launched initiatives such as the Marshall Plan to rebuild Europe, fostering economic stability and preventing the spread of communism. This marked a significant transition toward a leadership role in international affairs during the Cold War.