Well, no they won't be required, because the future generations will refuse to pay them. There will be civil unrest far before an entire generation will be put under indentured servitde.
Sadly I think you are right. There will be unrest and these unfunded liabilities will never be paid. Someone, most likely the elderly, will be shortchanged of promised Social Security and Medicare benefits.
Or, in the worst case,we could have a full blown revolution, and repudiation of all debts or liabilities by the former government.
We could also see runaway inflation, where debts get paid in worthless dollars.
But, something’s got to give. Liberals talk of sustainability in the carbon area. What about debt sustainability?