Nah, the bankers wouldn't stand for that. They get a commission on the transaction no matter which way it goes. But they may persuade China to accept Kalifornia instead: there's a lot more mortgages to foreclose on and eviction notices to serve. Bankers like that!
They can buy all the T-Bills they want. We can print the money to pay them back. Paper is cheap.
True, devaluation is another option... if you don't mind pushing a wheelbarrow full of money to the corner store just to buy a loaf of bread.
It's only devaluation if they spend the money. If they keep it under their mattress, it doesn't cause inflation. If they do spend it, it creates jobs. I'm still not worried.
China has their own banking problems. Bad loans to state owned companies that will never make a profit and never pay back the loans.
Kind of like U.S. steel companies.