Sad and desperate situation.
The U.S has no intention of paying anyone back. They have successfully suckered the whole of humanity to underwrite government largess on a massive scale and intend to not pay.
They are presently trying to inflate their way out through Quantitative easing, but have only caused a new stock market bubble. The fact is that most consumer and business demand is so low that their inflating of the money supply has caused the investors to simply run up the stock markets.