As the saying goes, "We'll survive by doing each others laundry". That saying, of course, is meant to be a joke. The US can't just do it's own laundry to survive. We can't just sell latte's to each other, either. We have to actually produce more than we consume.
So, we either have to produce a lot more, or consume a lot less. I don't see us producing more, do you?
I used to comfort myself that we had evolved as a nation, from doers into investors, and that we still brought value to the world by providing the capital needed for the rest of the world to grow, and so we were indeed, earning our bread. My faith in this viewpoint has been shaken, however.
All is not bread and circuses for non-US folks either. If the US consumer quits buying, I think that's a big deal to everybody.