Another week, another heretical speaker bullied and physically intimidated on an illiberal college campus.

Last week it was pro-police Manhattan Institute scholar Heather Mac Donald, who was invited to speak at Claremont McKenna College in California. Hundreds of protesters blocked the entrances to the building where she was scheduled to talk, chanting “Black lives matter,” “F--- the police” and “Shut it down.” Student journalists who tried to document the protest were swarmed, pushed and verbally threatened.

Mac Donald spoke via live-stream to a mostly empty room, as protesters banged on the windows and shouted; police cut the talk short and escorted her out of the building.

Just a few weeks earlier, conservative political scientist Charles Murray had been hounded by a mob at Middlebury College in Vermont. There, protesters sent his (liberal) faculty escort to the emergency room.

These are but the most recent examples of attempts to suppress speakers, viewpoints, teaching materials and works of art that students — usually liberal students — find “unsafe.”

Each time something like this happens, pundits make impassioned pleas that the solution to speech you abhor should be more speech, not less; that you must be brave enough to face your ideological enemies, not muzzle them; that the free exchange of ideas is critical to scientific and moral progress; that censorship is contrary to American values, included those enshrined in our Constitution.

Clearly, this appeal to high-minded principles and character development isn’t working.

So let’s try another tack: naked self-interest.

To today’s (predominantly liberal) college students, I offer five reasons that granting your ideological enemies a chance to speak benefits you, even — perhaps especially — when you believe their words are dangerous or hateful.

First, you’re giving the speakers you abhor a much bigger platform when you martyr them.

As I’ve written before, censorship tends to generate more public interest, not less, in whatever message is being censored. This is true for paintings as well as paid lecturers.

Professional troll Milo Yiannopoulos grew especially adept at monetizing this phenomenon. Violent protesters helped him gain attention, speaking gigs and (at least until his comments about sex with underage boys went viral) a book deal. He and other, more-principled conservatives would never have gained their large followings absent the telegenic hysterics of angry liberals.

Second, suppressing ideas you disagree with dulls your ability to cogently, convincingly rebut them.

If you want to win arguments — let alone elections — honing your rhetorical chops will be crucial. Getting up and asking a tough question at a speech is good practice. Especially for when you’re no longer able to call in an in-loco-parentis administrator to punish or expel your adversaries.

Third, and relatedly, you’re not actually crushing opposing views by shushing them; you’re merely forcing them underground, where they can fester and mutate into more dangerous forms.

It’s no wonder that so many campuses have struggled with nasty anonymous comments and harassment on apps such as Yik Yak. When students feel they can’t speak openly because they fear being branded a bigot or traitor, they turn to the anonymous fever swamps.

If you’re right, as you believe you are, it’s better to engage, argue and attempt to dissuade your opponents, out in the open. As Brookings Institution scholar Jonathan Rauch once put it, “Suppressing speech that’s wrong-headed and hateful is like curing global warming by breaking the thermometers. The root problem is fear and ignorance and hatred, and you go for that by correcting people.”

Fourth, you may not realize it yet, but you’re breeding resentment and reactionaryism — and turning potential allies into enemies.

Almost every time I have reported on some arbitrary campus purity test or purge (remember Sombrerogate?), students I’ve interviewed made some version of the following statement: “I consider myself [liberal/moderate/centrist], but this is making me more conservative by the day.”

President Trump’s jihad against political correctness not only appealed to those who long for the days when they could sexually harass their secretaries with impunity; it also resonated with some less regressive types who have soured on what they see as the left’s illiberalism and virtue-signaling. Don’t fuel the Trumps of the world by shutting down debate.

Finally, the same censorship tools you’ve developed to silence your enemies will be used against you.

Right-wing students and allies have already begun adopting tactics to intimidate intellectual enemies and muzzle ideas they dislike, including through trigger warnings, professor “watchlists,” proposed ideological litmus tests for college hiring and even speech codes.

Remember, liberal snowflakes. You’re playing the long game, which includes the day when you may no longer be in a position of power. Be smart. Before you have that debate tomorrow, from the minority position, set some fair ground rules today.