If the US goes “bankrupt” before the world, the world can’t actually do anything to get something back unlike an actual bankruptcy. The world will simply be stiffed. What that would look like, I cannot imagine.
Wanna bet? You'll need a suitcase full of money to buy a loaf of bread. Imports? forget it. Exports? They'll be very cheap. We'll become the "China of the west" working our butts of for what amounts to pennies a day compared to other currencies, and producing cheap junk- Government Motors cars etc. for the world.
Yes, that would be hard to imagine. If the bottom falls out of the dollar, perhaps the only way for the US to get the foreign goods it depends on would be to trade food.
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And don’t forget we’ll have very little real industry left, so the cheap stuff we will still be able to produce from what little resources we still have won’t be much. Get used to picking veggies, and oranges if you live in Fl. Maybe mining coal for china.
Then comes the repo man, aka war.