America has been here before. They survived great depression and god knows how many recessions, they survived the aftermath of vietnam war.
What america has:
1. huge land mass with huge natural resources and huge arable land.
2. a lead in the tech sector as shown with semiconductor and aeroplane industry
3. control of global financial system
The first and second factor alone can guarantee the americans the ability to bounce back from any problems they may face.
What america doesn't have is hostile neighbors surrounding it.
Again, I think we must never underestimate the yanks. We also need to do SWOT analysis on the US and on China.