There will be a lot of this. Same thing happened with Hillary. I'm not American, I don't need to discriminate here, I'm writing off all of the US.
But if you're there... yeah, that anger seems justified. When the shit that's about to happen happens don't let them hide behind the blame game.
Yeah, no, we're on the same page. Whether you pin it on the OP or Piker. There are a bunch of presumably leftist pundits that have been asking to see the left's management all through this process (and I mean since 2016) and will continue to act offended that anybody would suggest there is a responsibility in not being persuaded when the alternative is a fascist anarchocapitalist cabal.
As last time, the response to any mention of this will be "it's their fault for not convincing me", which has never been a legitimate argument but will be outright insulting if (when) things start to go poorly.
A better case is that the entire country shifted right, especially fed by a mass of new protofascist youth, but you don't get extra credit for only being part of the problem and not the whole problem.
In any case, like I said earlier, I have no obligation to split hairs. The US has failed as a country and as a people. They can apportion blame however they see fit. For the rest of us it is now a matter of how to build an international community of democracies in the upcoming climate. We all have to write off the US and find a new way forward without them.