I agree that fear is the more profound emotion here, not anger. Though it is provoked by the same "fight or flight" reflex.
The world is changing, and has changed, so fast that some people don't feel comfortable in it anymore. That anxiety prompts a move to emotional decisions rather than rational evidence-based ones. To be part of a tribe targeting a rival tribe, rather than be confident enough to back your own analysis. To romanticise the past, and pretend it was better than it was. To demonise the "other", because they are different to you. To pretend that everything is terrible when the other guys are in power and everything is great when your guys are in power.
