Well, here is one thing about national debt, and it applies to the money we owe AND the money we are owed.
It is exceedingly rare for a situation to exist whereby the creditor can simply "call in" the loan.
Most debt has structured payments by installments. I don't know much about the debt that is owed to us, but I do know that in terms of the debt we owe, we have not been late on a payment or missed a payment, including interest. It is for this reason that America remains solvent despite a gross debt (that is, a national debt BEFORE the debt that is owed to us is subtracted from it) that exceeds our GDP. Think of it as a person who has a mortgage. If you have a mortgage, you owe a hell of a lot of money, right? So you're broke, right? Nope.
Well, in America's case, the value of the mortgage we are paying on has only just recently surpassed our GDP, which in this analogy could be considered "a year's pay."
This analogy works both ways. In terms of our debt, we're the one with a mortgage. In terms of debt owed to us, we're the bank. In both cases, as long as the payments are made on time then the bank cannot simply say "alright, pay up."
So in short, your solution doesn't 100% work, but that's okay because the problem it was intended to solve has been overblown anyway.

All that aside, this is useful information, and I've always wondered how much money is owed TO the U.S, instead of BY the U.S.