The Crash of 1929 made the country even more inward looking...The protectionism bills passed during that time prolonged the depression. While other countries armed themselves and madman grew in power the USA did nothing. Our foreign holdings taken at the turn of the century like the Philippines was understaffed, our navy was forgotten.
We were ill prepared for WW2 and could not project power around the world to stop it form starting......
For the last 70 years American’s engagement in the world has stopped another world war from starting. The wars have been brief and local. Do you think without the USA and NATO the USSR would be gone form the face of the world?
Wilson got us into WW1 to bail out Great Britian right after the bastard lied through an election about keeping us out.
Versailles was a travesty. The League of Nations was a joke just as is the UN.
Besides, we are broke.
Bankrupted by empire-like overreach, like Spain and France and Britian before us. History keeps repreating
The Wall fell in 1989 and yet NATO is still around.
That's part of the problem, like any government program it outlives its problem.