Liberals are part of a political cult with the DNC and New York Crimes at the head. They have absorbed the dictates of their cult leaders such that they reflexively reject all criticism and compare it to wanting the worst thing conceivable (to them) to happen, i.e. Trump winning again.

They don't have to think about the things you mention because their media bubble does not tell them to nor does it emphasize these things as bad or harmful. Their bubble says murdered Palestinians were killed in the passive voice and Israelis are killed by "terrorists". Their bubble barely talked about Yemen at all during the Obama years and their responses to hearing about it are usually bewilderment and frustration that they don't have a snappy comeback ready for "Obama killed a bunch of kids by starving an entire country". The Crime Bill doesn't mean anything to most liberals, they don't even know that it is or what it did. It's an amorphous blob that other people say is bad and rather than learn anything about it they just change the subject.

Liberals can be rescued from their cult but they have to get over the main hurdle they constructed at the behest of their masters: incredible arrogance and incuriositu. It can be challenging to knock them off their little pedestal constructed of Washington Post Op-Eds saying the Democratic primaries should be less democratic and all poor people deserve what they get. They have to be slapped with something and clearly a blatant genocide isn't enough - they still turned to their masters and lapped up the false narratives. Their boy being senile is having a greater impact because while it runs against their years-long excuses given against the left pointing out the obvious, it reconfirms their practice of, "politics is a team sport horse race" that makes them feel oh so very smart. They don't have to make a very big adjustment like caring about dead brown people.