UC-Berkeley this week canceled an April 27 Ann Coulter speech, fearing riots. This lunacy will only grow until colleges start standing up decisively for free speech.

The school is trying to negotiate a new date, venue and ground rules with the group that invited her, but so far has failed.

Its worry is obvious: Masked, rock-throwing thugs prevented a February speech by Milo Yiannopoulos. And the area saw 20 arrests last weekend as extremists of left and right battled in the streets.

But the answer to disorder is order: Put on extra security; keep non-students far from the campus event — and have the police trained and ready for trouble.

Berkeley’s move follows the Black Lives Matter disruption of a UCLA speech by the Manhattan Institute’s Heather Mac Donald, and efforts to muzzle her the next night at Claremont-Pomona College — 200-odd protesters chanting “Shut it down!” and “From Oakland to Greece, f - - k the police.”

Last month, goons stopped American Enterprise Institute scholar Charles Murray from delivering a moderately conservative talk at Middlebury College, with Professor Allison Stanger hospitalized by the violence.

More and more college students think it’s proper to act out this way. They proudly deny the free-speech rights of people whose writings they haven’t even read. (The Wellesley Review blather that we noted on Sunday is among the more coherent of these screeds; others are painfully ignorant.)

The kids are plainly learning this nonsense at college — which means professors and administrators are failing at their most fundamental duties.

If they’re even trying.

Worse, all this is surely the public tip of the iceberg: How much worse is it in the classrooms?

Increasingly, US campuses are the exact opposite of the bastions of free thought and debate they’re supposed to be. If the schools can’t save themselves, society has every right to demand new management.