It would float on world markets the same way every other currency does. I suspect that a compromise would saddle each new nation with a portion of that debt. One of the gravest reasons for concern is the rise of a Communist China determined to reclaim Taiwan and establishing its hegemony in Asia regardless of cost. This is the same bugaboo the federalists relied upon to raise fears about the Articles of Confederation. Essentially, the claim is that, in order to ward off tyranny from abroad, we must accept tyranny here at home.
Fear is the passion of slaves.
Yes, I wish Taiwan would remain free of Chinese control. The libertarian foreign policy solution to Taiwan is to offer safe passage to the United States for all islanders who want to move, and then leave that mess alone. The main reason China may be able to engage the United States is the country's economic development. It is true that the Chinese have been stealing secrets from the United States. However, the solution to this problem is not bound up with the matter of secession.