Two emotions: fear and greed. How far did each of these forces shape and define

Two emotions: fear and greed. How far did each of these forces shape and define American history in the twentieth century? Which one was stronger? And in those two, do we have the perfect, complete explanation of why America did what it did, didn’t do what it didn’t do, and turned out as it turned out? Really? (Mind you, this isn’t just a domestic policy question).
This is what it needs to be about, its just a long essay and needs to be perfect