The cancellation Wednesday of a speech by right-wing provocateur Milo Yiannopoulos at UC Berkeley was, according to a university spokesman, “not a proud night for this campus, the home of the free speech movement.”

That’s putting it mildly. Even if the cancellation was justified by concerns about public safety after an outbreak of violence and property destruction, the fact that Yiannopoulos was prevented from speaking to a willing audience of campus Republicans should make supporters of free speech shiver.

In a characteristically knee-jerk reaction to Wednesday’s events, President Trump tweeted: “If U.C. Berkeley does not allow free speech and practices violence on innocent people with a different point of view — NO FEDERAL FUNDS?”

That would be a ludicrous overreaction even if it were true that the university had been on the wrong side of the issue. But actually, UC Berkeley Chancellor Nicholas Dirks had steadfastly defended the right of the Republicans to invite Yiannopoulos to speak, rejecting a request by a group of professors that the Breitbart News writer’s appearance be canceled because he engaged in “hate speech” and, based on his appearance at another university, might harass or belittle individual students.