Students at a growing number of U.S. colleges are gathering in protest encampments with a unified demand of their schools: Stop doing business with Israel — or any companies that empower its ongoing war in Gaza. The demand has its roots in a decades-old campaign against Israel’s policies toward the Palestinians. The movement has taken on new strength as the Israel-Hamas war surpasses the six-month mark and stories of suffering in Gaza have sparked international calls for a cease-fire. Inspired by ongoing protests and the arrests last week of more than 100 students at Columbia University, students from Massachusetts to...