The commitments on antisemitism made by Columbia University under pressure from the Trump administration mark the first time in nearly 23 years that the university has come close to acknowledging the problem on its campus. Heretofore it has belittled the concerns. Only five years ago, its former president, Lee Bollinger, declared that assertions by outsiders that Columbia had become an “anti-Semitic institution” were “preposterous.”

Our own view is that in some narrow definition of “preposterous,” Mr. Bollinger’s boast was not wrong so much as inapt. It would have been one thing had he adequately addressed the problem at Columbia. For years he shrank from that, a context in which his comment was off the point. It was dismissive of the seriousness of what had begun to fester in the Middle East studies department and that was exposed by students operating as “The David Project.”