China may own a large part of our debt, and maybe other countries also, but IOUs aren't worth much in fiat money.
The US only has 2 real assets. Land and people. And China has enough of their own people.
The only consolation I have in all this union bailout crap is that both China and the unions will eventually get screwed when we pay China back with inflated $'s and the union's fixed income payments get crushed by the inflation they had a large hand in creating...