Maryam Alwan figured the worst was over after New York City police in riot gear arrested her and other protesters on the Columbia University campus, loaded them onto buses and held them in custody for hours.But the next evening, the college junior received an email from the university. Alwan and other students were being suspended after their arrests at the “ Gaza Solidarity Encampment,” a tactic colleges across the country have deployed to calm growing campus protests against the Israel-Hamas war.The students’ plight has become a central part of protests, with students and a growing number of faculty demanding their...