The images of the recent protests at Columbia University have grabbed the attention of the American public: students chanting for a Palestinian state, “from the river to the sea”; activists setting up a mass tent encampment on the campus lawn; masked occupiers seizing control of Hamilton Hall. For some, it was a sign that ancient antisemitism had established itself in the heart of the Ivy League. For others, it was déjà vu of 1968, when mass demonstrations last roiled campus. Columbia president Minouche Shafik feigned surprise. In a statement to students, she expressed “deep sadness” about the campus chaos. But...