The core of the issue is the "Just World Fallacy" sometimes also called the "Prosperity Doctrine" and a few other things. It boils down to one core idea "Good things happen to good people, and bad things happen to bad people." Basically, everyone tends to think of themselves as, more-or-less, good people. So when bad things happen, as they inevitably do, these people start going "Huh, more bad stuff is happening to me than I've done bad things. WTF?" So, they come to a reasonable if flawed conclusion that "someone ELSE is doing bad things, and I'm collateral damage." This isn't entirely wrong, although sometimes bad things do just happen. However, since at least as far back as the Civil War (and probably since time immemorial), the people whose fault it REALLY is (i.e., the people with power and privelege) have pointed at outgroups, commonly immigrants but also slaves or Catholics or trans people, and said "THOSE people are being bad. THOSE people are why you are suffering. Give me more power and I'll get rid of THOSE people."