Jordan Peterson has pointed out that there’s a destructive positive feedback loop operating these days — my outrage doesn’t convince you to rethink your position, it only encourages you to ratchet up your own. He is on to something.
So we manage to convince ourselves that the evidence speaks so loudly, so emphatically, that we have no choice but to declare our allegiance to a particular tribe as a result of that evidence. The red tribe. Or the blue one. Or the white one. Or the black one. It rarely crosses our minds to notice that causation is probably going the opposite direction — the tribe we are in determines the evidence we notice and accept.
The underlying problem is very old. Most of us know very little. The world is a complex place and it’s hard to know what is going on. So we grope around in the dark trying to make sense of what is happening and what explains what we observe. We manage to convince ourselves that we are seeking the truth and we have found it. Trump is evil or Hillary is evil. Black people are the victims of a conspiracy by white people to oppress them or white people are being marginalized as their majority status dwindles. The country is on the wrong track. (Everyone believes this one). And subtlety is not our strong suit as human beings. We like simple stories without too much nuance.