These little tyrants are the bastard offspring of older radicals.

Video footage of Yale students losing the plot over a faculty head and his wife, who said everyone should calm down about Halloween, has caused much head-shaking in liberal circles. And it isn’t hard to see why. The head’s crime was that his wife sent an email suggesting academics and students should chill out about ‘culturally insensitive’ Halloween costumes. It’s okay, the email said, to be a ‘little bit inappropriate or provocative or, yes, offensive’ on this one day. For his wife issuing this mildest of rebukes to over-sensitive over-18s, the head was accosted by a mob of students insisting the email made them feel unsafe. When he told the crowd that he thinks university is about providing education, not a ‘safe home’, they screamed at him to ‘step down!’. ‘Who the fuck hired you?!’, the most unhinged of the students cries.

It’s unnerving, odd, a terrifying snapshot of the new intolerance. We could see the culture of ‘You can’t say that!’ in all its swirling, borderline violent ugliness. It wasn’t a whispered or implied ‘You can’t say that!’, of the kind we see all the time in 21st-century public life, in response to people who criticise gay marriage, say, or doubt climate change. No, this was an explicitly stated ‘You can’t fucking say that, and if you do we’ll demand that you be sacked!’ That it was stated at Yale, and in response to a bloody email about Halloween, has added to the hand-wringing among liberals, who want to know what’s gone wrong with the new generation.