If your $1,000 in debt, you have a problem, if your 100 billion in debt, the bank has a problem, if your north of 35 trillion in debt, who has the problem?
The national debt makes this question almost impossible to answer because it doesn't work the way normal debt does. It's basically just a way for the fed to plan to spend money in the future, since everything they do is long term.
The vast majority of the debt is owed internally to US taxpayers, corporations, and in some cases the government owing other parts of the government. These are the same people and corporations that the government taxes to
pay these debts right back to them. So if debtholders "call in" this debt guess how the government pays for it? By taxing those very same people. The money never went anywhere and never ended up anywhere.
Since the fed can print money and make laws, buying things by just handing people cash doesn't work. They have to give people a "stake" in the nation's well being because that gives people actual leverage over the fed, like selling stocks.
None of this is to say it's impossible for the national debt to be too high like a lot of Keynesian worshippers believe but the idea that the country is trillions "in the hole" and we all have to climb our way out isn't even just misleading but outright false. That debt clock thing that calculated "this is how much your family owes" is bullshit. You don't owe squat,
the government owes you.
So to answer the question, everybody owes everybody else so nobody has a problem. It's just a bullshit way to decide what leverage different people have over the future. You might just say the debt is fake and gay.
Edit: I am starting wonder how much Elon understands this, most politicians lie through their teeth about how it works to get votes, but I'm starting to think Elon might actually be so dense he thinks we owe all of that to China.