This might seem like an abrupt and mysterious reversal in campus culture. In fact, it’s a sign that student protest was never a fact of nature, but rather an administrative choice. Universities chose to let campus demonstrations get out of control; now they’re choosing to suppress them. This is why, even as legal challenges have blocked the Trump administration from enacting much of its higher-education agenda, the president has clearly achieved his aim of ending the protest movement. He has been able to do so largely because university leaders, tired of the chaos they had allowed to thrive, were quietly on board.