It’s my understanding that debt is mostly held in the US by Americans and that a country that runs a debt in a currency it controls isn’t anything like household debt.
That said, what would it mean for the US to go bankrupt?
No, it's not. This is a fundamental misunderstanding of many people who get ginned up about this. Debt is the most powerful tool of a nation.
The US is a sovereign, the sovereign. The country can borrow until the faith and credit in our ability to pay is lost. There's no such thing as bankruptcy, you can default or print money.
The US is rocketing towards depression. Slowing down the velocity of money is the single worst thing you can do for an economy. We're implementing the largest tax increase in history, taking away pensioner benefits, and pushing the cost of healthcare up, nuking consumer demand. There's no adults keeping Trump away from doing stupid shit -- he'll set off an economic death spiral.
If you took everyone with >100M in net worth, put them up against the wall, and seized every dime they own, you'd get ~30T (in a best-case scenario). Even if you used it to pay off the debt, we'd still be running trillion-dollar deficits every year.
If our debt and deficits are a revenue problem, they are objectively insoluble.