NEW YORK — Night after night, Columbia University student Sonya Poznansky fell asleep to the sound of her peers chanting to “globalize the intifada,” a mantra that at best brings back images of the bloody Palestinian uprising of the early 2000s, and at worst can be interpreted as a call to repeat the violence against Jews worldwide. “In those moments, I kept thinking about my great-grandmother, who left Poland in 1925. What signs did she see that made her feel there wasn’t a future for her family there?” she said. Upon graduation, Poznansky reached the same conclusion her great-grandmother did:...