So how do we build confidence anyhow when we can't know everything?

I think first, standard checks - does it compile? What do static analysis tools say - code quality, passes SAST analysis? Linters? Style checkers?

Do the tests run? I'm not comfortable with the tests I write let alone the AI.. by adding fault injection (fuzzing, chaos), and mutation testing, I have a better degree of confidence in the tests and code.

Spend even more time getting to know the product instead. Maybe I don't know the code as well as I used to, but I know the product backwards and forwards. That helps me have some new confidence that I didn't really have before. Knowing the greater whole.

The hopeful part of me thinks that what will emerge from the disorder will be better, just like anything else that survives today that was once part of something else.

Not to mention that even with a strong leader in both parties, we are on a race to the bottom, each election oscillating between the two parties, each spending lots of money and focus undoing what the other party did. When the two parties had common ground, this was much less of an issue.

In the end, this isn't going to get fixed, the US is going to just keep printing money, blowing up the deficit until the last few countries outside the US who trust us no longer do. We'll be in too many wars, in too many places, with too few friends. End up the same way the USSR was when they were in Afghanistan for too long.

I don't think even if you pulled money out of politics, banned stock trading for elected officials, no foreign wars, universal health care - that we would right the ship. Our problems are fundamental. Our early leaders warned us against a two-party system, trying to show us the problems it would lead to, and we ignored it.