International students at Columbia feel unsafe expressing opinions

International students and faculty at Columbia University are increasingly silent following a crackdown on pro-Palestinian protests. Federal agents have arrested two foreigners, including a student, and revoked another student's visa, causing fear among the international community. Columbia's Graduate School of Journalism reported an "alarming chill" among foreign students, who feel unsafe expressing their opinions. Other universities are advising international students to be cautious about their speech and online activity due to potential immigration consequences. The Trump administration's actions have raised concerns about free speech and the treatment of non-U.S. citizens. Immigration authorities have escalated their activities, with more visa revocations expected in the coming days.