The common-humanity form of identity politics can still be found on many college campuses, but in recent years we’ve seen the rapid rise of a very different form that is based on an effort to unite and mobilize multiple groups to fight against a common enemy. It activates a powerful social-psychological mechanism embodied in an old Bedouin proverb: “I against my brothers. I and my brothers against my cousins. I and my brothers and my cousins against the world.”
