Federal immigration authorities have detained Mahmoud Khalil, a pro-Palestinian activist and recent graduate of Columbia University, who has legal permanent residency in the United States. This arrest is seen as a significant escalation of President Trump's crackdown on what he has called antisemitic campus activity. Khalil's lawyer confirmed that he is a green card holder and that they will be pursuing his rights in court. The Trump administration has made Columbia the first target of its push to punish elite schools for their failures to protect Jewish students during campus protests.