Math doesn't care about anyone's politics. The money has been spent, the debt has piled up, and sooner or later, unless we believe in fairy tales, the piper will be paid.
It's possible that "sooner or later" will be later enough that the world will change in fundamental ways that alter the math.
We've seen it happen multiple times in the last couple centuries. An industrial revolution, end of slavery, world wars, etc. The real folly is thinking that there can't be another cataclysmic or other world-altering event in the next 50 years. It'll probably be climate change - something we are very well positioned to mitigate and adapt to, that most of the rest of the world isn't and can't.
This isn't a defense of our excessive spending, or the stupid burden of debt we've saddled our kids with.
I've written this before here: imagine you're an alien, visiting the uncharted backwaters of the unfashionable end of the Western Spiral arm of the Galaxy, and orbiting a small unregarded yellow sun at a distance of roughly ninety-eight million miles is an utterly insignificant little blue-green planet. They're observing ape-descended life forms competing for scarce resources. On one continent, let's call it North America, you have a bunch of monkeys who've spent the last century importing natural resources from other continents, which they'd "paid for" with promises and little green pieces of paper.
Who do you think the aliens will conclude is "winning" that exchange?
Objectively, we're doing OK,
even if we default ...
We have all the advantages. Geography, natural resources, technology, military, capitalism, functioning democracy, a disproportionate share of the best universities in the world, industry, agriculture, eager inexpensive immigrant labor from the south, polite people living to the north, two really big ocean moats between us and the places that burn with war and famine every so often.
As for servicing the debt, keep in mind that (1) it doesn't all reset to a new interest rate twelve seconds after the Fed acts to raise rates, and (2) we have an exceptionally low tax burden by global standards with room to go up.
Nobody knows exactly how or when this will play out. But if you're stocking the bunker in the compound, maybe choose foodstuffs with a 30-year shelf life as opposed to a bunch of avocados or bananas. The first thing to prepare for is long and boring retirement.