This is mostly because Americans keep electing total morons.

I would actually suggest this is symptomatic of the real problem: money in politics.

Elected officials (and some appointed, like SCOTUS) keep changing laws and precedents to allow more and more money in politics. They can't quit all that dark money - without a lot of funding, you don't get elected. Usually the best funded candidate wins.

There was an anonymous oped from a congressman some years back which bemoaned the reality - that 60% of their time was dedicated to meeting with donors for reelection campaigns instead of working on real problems.

Not that most other nations do dramatically better, alas.