Joining the United Nations and participating in NATO represented a shift in U.S. foreign policy from isolationism to being more active in the international scene.
The U.S. decided to abandon its isolationist policies and engage in international affairs as a result of its status as a superpower.
It showed this shift by joining the United Nations as well as participating in NATO to protect her allies.
Find out more on U.S. Isolationism at https://brainly.com/question/14848631.
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