Something I picked up in era of machine learning is why humans are so terrible at making long term decisions - if artificial neural nets model how our minds work even a little bit it is a miracle that humans are capable of symbolic logic and long-term decision making outside of ritual.

That makes this sort of thing annoying. The odds of arriving at "why did this happen?" through rational discourse are very slim. However, I do recall a number of years ago people making arguments like "lol what are they going to do, leave?" and it appears that was wrong. And I would encourage people who are gung-ho about US debt overall to reassess their beliefs in light of that - it doesn't look like the money was invested productively to me and it is a dangerous assumption that there will be wealthy people around to pay off someone else's stupid spending.

But the real problem here is not that the current policies don't create enough wealth. That is a problem, but the real problem would have been a decade or more ago. It is like when the local dam runs out - risky decisions and bad principles would have taken root decades ago that were, in hindsight, risky and reckless.