An article here:

As of last June (the latest complete breakdown available), the biggest holder of Treasury debt was the U.S. government itself, with about 52 percent of the total $8.5 trillion in paper that's out there. Most of the government’s holdings are massive savings accounts for programs like Social Security and Medicare. Just as you may prefer to keep your Individual Retirement Account in the safe Treasury bonds, the folks who manage the Social Security Trust Fund are looking for a secure investment, too.

So yes, Virginia, the huge entitlement trust funds do, in fact, consist of IOUs.

That’s leaves a little over $4 trillion in public hands. The biggest chunk (about 25 percent of the $8.5 trillion total) is held by foreign governments. Japan tops the list (with $644 billion), followed by China ($350 billion), United Kingdom ($239 billion) and oil exporting countries ($100 billion).

Other big holders of Treasury debt include state and local governments ($467 billion); individual investors, including brokers ($423 billion); public and private pension funds (319 billion); mutual funds ($243 billion); holders of US savings bonds ($206 billion); insurance companies ($166 billion) and banks and credit unions ($117 billion.)

The link given in the article is dead, so let's assume for the sake of argument that ALL the "oil exporting countries" in the list are hostile to us (in fact it probably includes Canada).

That would make $450 billion out of $8.5 trillion that we owe o "hostile" countries.

That's about 5 percent. If we're just talking China, that's about 4 percent.

"China owns the U.S. debt." Another one of many, many things that "everybody knows" that's dead wrong.