It was only a matter of time before Richard Dawkins fell victim to the no-platforming trend, wherein universities and organizations publicly disinvite people to events because of their “offensive” opinions.

Dawkins, the renowned evolutionary biologist and world-famous atheist, has frequently been targeted by cultural conservatives for his incendiary tweets.

The latest to catch fire—a cartoon video satirizing Islamism and feminism that Dawkins retweeted—cost him his invitation to speak at the annual Northeast Conference on Science and Skepticism (NESCC) in May.

The video is indeed controversial: it relies on stereotypes of Islamic and feminist ideologies to criticize them at their most extreme (in this case, a feminist and an Islamist singing a duet about how marginalized they both are—“a whiny pair of little spastics”).

Feminists on Twitter were incensed, even more so when the author Lindy West pointed out that the woman depicted in the cartoon was inspired by a Canadian feminist who received rape and death threats after protesting at a Men’s Rights group event in Toronto.

When West presented Dawkins with this information, he deleted his original tweet of the video and clarified his position.

“Having learned that the woman in the joke song is a real person who has been disgracefully threatened with violence, I’m deleting my tweets,” he wrote. “PLEASE PLEASE PLEASE don’t ever threaten anyone with violence. We should be free to use comedy/ridicule without fear it may inspire violence.”

The apology was not enough for those organizing the NESCC, who issued a statement condemning Dawkins’ “approving re-tweet of a highly offensive video. We believe strongly in freedom of speech and freedom to express unpopular, and even offensive, views. However, unnecessarily divisive, counterproductive, and even hateful speech runs contrary to our mission and the environment we wish to foster at NECSS.”

NECSS did not respond to requests for comment from The Daily Beast.

The question isn’t why Dawkins was disinvited from an event (anyone whose views or actions are in any way controversial is susceptible to this trend of intolerance), but why now?

After all, Dawkins has been excoriated for tweets about pedophilia (“Mild pedophilia is bad. Violent pedophilia is worse. If you think that’s an endorsement of mild pedophilia, go away and learn how to think.”); a similar tweet stating “Stranger rape at knifepoint is worse” than date rape (“If you think that’s an endorsement of date rape, go away and learn how to think.”); a tweet attacking “Muslims” for “segregating the sexes” during a debate at University College London; a series of tweets expressing skepticism about a Texas teenager, Ahmed Mohammed, whose school project was mistakenly thought to be a bomb; snarky tweets about Islam’s treatment of women, Islamic scholars (“True scholars have read more than one book”), and so on.

Dawkins’ critics are right to point out that generalizing about Muslims--and he has done so many times—can provoke racism; likewise to point out the muddy ethics of caricaturing a real person in satire. (To be fair, when Dawkins learned that the feminist in the cartoon was modeled on a real person who had allegedly been threatened with violence in the past, he deleted his tweet of the video.)

Still, the offense was deemed to be unforgivable, and Dawkins—one of the most eminent scientists and skeptics in the world—was swiftly banned from speaking at the Northeast Conference on Science and Skepticism.

“I do not write this out of concern about my appearance or non-appearance at NECSS, but I wish there had been a friendly conversation before such unilateral action was taken,” Dawkins wrote in a statement. “It is possible I could have allayed the committee members’ concerns, or, if not, at least we could have talked through their objections to my tweet.

“If our community is about anything it is that reasoned discussion is the best way to work through disagreements...I wish the NECSS every success at their conference. The science and scepticism community is too small and too important to let disagreements divide us and divert us from our mission of promoting a more critical and scientifically literate world.”