A crackdown on foreign students is alarming colleges, who say the Trump administration is using new tactics and vague justifications to push some students out of the country. College officials worry the new approach will keep foreigners from wanting to study in the U.S. Colleges across the country have been startled to find that some of their students are being ordered to leave the U.S. — often without warning. Some have been targeted for pro-Palestinian activism or criminal infractions, while others have been left wondering how they ran afoul of the government. President Donald Trump campaigned on a promise to deport foreign students involved in pro-Palestinian protests.