Question

How did workd war 2 imfluence the change in identity of the U.S

Answer 1

WWII America watched everyone fight it out and when Germany was about to lose came in and stole the credit
The destruction of Europe again completely made Europe weaker than US.
Distrust of the Russians, US refused to help the USSR when they could have easily done so to build up trust.
So in the end the only superpowers remaining were the US and USSR and in any situations there can only be 1 leader of a world. Both competed to be the best which leads to the arm race and the cold war. But soon the US outcompeted them and became what it is today.
The world superpower that creates a mess all over the world to promote its own interests