They are perfectly able to consume their own shit. As the dollar loses value all other currencies will gain value. There will certainly be some turmoil for everyone during the transition period, but once the dust settles those who own the appreciating currencies will be able to outbid americans.

You're also forgetting that US is consuming on borrowed money. The countries that are exporting the products are the same countries that are lending you the money to buy them. When they stop with this they'll have a lot more money to move around with. Since americans spent most of their borrowed money on unproductive consumption and false wealth (dotcom stocks and houses) it's impossible to pay back their current debts. No one is going to keep lending money in those conditions.