The article goes into specifics, but the general premise is as old as humanity. The subtitle: "The new political polarization casts rivals as alien, unlikable a

The article goes into specifics, but the general premise is as old as humanity. The subtitle: "The new political polarization casts rivals as alien, unlikable and morally contemptible" This is tribalism at its core. It's baked into us for evolutionary reasons that helped us survive, but is now a detriment.