At No 5 in the Spectator's most-read articles for 2015 is Brendan O'Neill's cover piece describing 'Stepford Students': those who want to shut down debate when it involves people they disagree with and arguments they don't like. Brendan spotted this phenomenon in 2014 but his article returned to our best-read list this year as more and more people cottoned on to the trend for 'safe spaces' and no-platforming in our universities. And it spawned a website edited by defiant Stepford Students.

Have you met the Stepford students? They’re everywhere. On campuses across the land. Sitting stony-eyed in lecture halls or surreptitiously policing beer-fuelled banter in the uni bar. They look like students, dress like students, smell like students. But their student brains have been replaced by brains bereft of critical faculties and programmed to conform. To the untrained eye, they seem like your average book-devouring, ideas-discussing, H&M-adorned youth, but anyone who’s spent more than five minutes in their company will know that these students are far more interested in shutting debate down than opening it up.

I was attacked by a swarm of Stepford students this week. On Tuesday, I was supposed to take part in a debate about abortion at Christ Church, Oxford. I was invited by the Oxford Students for Life to put the pro-choice argument against the journalist Timothy Stanley, who is pro-life. But apparently it is forbidden for men to talk about abortion. A mob of furious feministic Oxford students, all robotically uttering the same stuff about feeling offended, set up a Facebook page littered with expletives and demands for the debate to be called off. They said it was outrageous that two human beings ‘who do not have uteruses’ should get to hold forth on abortion — identity politics at its most basely biological — and claimed the debate would threaten the ‘mental safety’ of Oxford students. Three hundred promised to turn up to the debate with ‘instruments’ — heaven knows what — that would allow them to disrupt proceedings.

Incredibly, Christ Church capitulated, the college’s censors living up to the modern meaning of their name by announcing that they would refuse to host the debate on the basis that it now raised ‘security and welfare issues’. So at one of the highest seats of learning on Earth, the democratic principle of free and open debate, of allowing differing opinions to slog it out in full view of discerning citizens, has been violated, and students have been rebranded as fragile creatures, overgrown children who need to be guarded against any idea that might prick their souls or challenge their prejudices. One of the censorious students actually boasted about her role in shutting down the debate, wearing her intolerance like a badge of honour in an Independent article in which she argued that, ‘The idea that in a free society absolutely everything should be open to debate has a detrimental effect on marginalised groups.’

This isn’t the first time I’ve encountered the Stepford students. Last month, at Britain’s other famously prestigious university, Cambridge, I was circled by Stepfords after taking part in a debate on faith schools. It wasn’t my defence of parents’ rights to send their children to religious schools they wanted to harangue me for — much as they loathed that liberal position — it was my suggestion, made in this magazine and elsewhere, that ‘lad culture’ doesn’t turn men into rapists. Their mechanical minds seemed incapable of computing that someone would say such a thing.

Their eyes glazed with moral certainty, they explained to me at length that culture warps minds and shapes behaviour and that is why it is right for students to strive to keep such wicked, misogynistic stuff as the Sun newspaper and sexist pop music off campus. ‘We have the right to feel comfortable,’ they all said, like a mantra. One — a bloke — said that the compulsory sexual consent classes recently introduced for freshers at Cambridge, to teach what is and what isn’t rape, were a great idea because they might weed out ‘pre-rapists’: men who haven’t raped anyone but might. The others nodded. I couldn’t believe what I was hearing. Pre-rapists! Had any of them read Philip K. Dick’s dystopian novella about a wicked world that hunts down and punishes pre-criminals, I asked? None had.

When I told them that at the fag-end of the last millennium I had spent my student days arguing against the very ideas they were now spouting — against the claim that gangsta rap turned black men into murderers or that Tarantino flicks made teens go wild and criminal — not so much as a flicker of reflection crossed their faces. ‘Back then, the people who were making those censorious, misanthropic arguments about culture determining behaviour weren’t youngsters like you,’ I said. ‘They were older, more conservative people, with blue rinses.’ A moment’s silence. Then one of the Stepfords piped up. ‘Maybe those people were right,’ he said. My mind filled with a vision of Mary Whitehouse cackling to herself in some corner of the cosmos.

If your go-to image of a student is someone who’s free-spirited and open-minded, who loves having a pop at orthodoxies, then you urgently need to update your mind’s picture bank. Students are now pretty much the opposite of that. It’s hard to think of any other section of society that has undergone as epic a transformation as students have. From freewheelin’ to ban-happy, from askers of awkward questions to suppressors of offensive speech, in the space of a generation. My showdown with the debate-banning Stepfords at Oxford and the pre-crime promoters at Cambridge echoed other recent run-ins I’ve had with the intolerant students of the 21st century. I’ve been jeered at by students at the University of Cork for criticising gay marriage; cornered and branded a ‘denier’ by students at University College London for suggesting industrial development in Africa should take precedence over combating climate change; lambasted by students at Cambridge (again) for saying it’s bad to boycott Israeli goods. In each case, it wasn’t the fact the students disagreed with me that I found alarming — disagreement is great! — it was that they were so plainly shocked that I could have uttered such things, that I had failed to conform to what they assume to be right, that I had sought to contaminate their campuses and their fragile grey matter with offensive ideas.

Where once students might have allowed their eyes and ears to be bombarded by everything from risqué political propaganda to raunchy rock, now they insulate themselves from anything that might dent their self-esteem and, crime of crimes, make them feel ‘uncomfortable’. Student groups insist that online articles should have ‘trigger warnings’ in case their subject matter might cause offence.

The ‘no platform’ policy of various student unions is forever being expanded to keep off campus pretty much anyone whose views don’t chime perfectly with the prevailing groupthink. Where once it was only far-right rabble-rousers who were no-platformed, now everyone from Zionists to feminists who hold the wrong opinions on transgender issues to ‘rape deniers’ (anyone who questions the idea that modern Britain is in the grip of a ‘rape culture’) has found themselves shunned from the uni-sphere. My Oxford experience suggests pro-life societies could be next. In September the students’ union at Dundee banned the Society for the Protection of Unborn Children from the freshers’ fair on the basis that its campaign material is ‘highly offensive’.

Barely a week goes by without reports of something ‘offensive’ being banned by students. Robin Thicke’s rude pop ditty ‘Blurred Lines’ has been banned in more than 20 universities. Student officials at Balliol College, Oxford, justified their ban as a means of ‘prioritising the wellbeing of our students’. Apparently a three-minute pop song can harm students’ health. More than 30 student unions have banned the Sun, on the basis that Page Three could turn all those pre-rapists into actual rapists. Radical feminist students once burned their bras — now they insist that models put bras on. The union at UCL banned the Nietzsche Society on the grounds that its existence threatened ‘the safety of the UCL student body’.

Stepford concerns are over-amplified on social media. No sooner is a contentious subject raised than a university ‘campaign’ group appears on Facebook, or a hashtag on Twitter, demanding that the debate is shut down. Technology means that it has never been easier to whip up a false sense of mass outrage — and target that synthetic anger at those in charge. The authorities on the receiving end feel so besieged that they succumb to the demands and threats.

Heaven help any student who doesn’t bow before the Stepford mentality. The students’ union at Edinburgh recently passed a motion to ‘End lad banter’ on campus. Laddish students are being forced to recant their bantering ways. Last month, the rugby club at the London School of Economics was disbanded for a year after its members handed out leaflets advising rugby lads to avoid ‘mingers’ (ugly girls) and ‘homosexual debauchery’. Under pressure from LSE bigwigs, the club publicly recanted its ‘inexcusably offensive’ behaviour and declared that its members have ‘a lot to learn about the pernicious effects of banter’. They’re being made to take part in equality and diversity training. At British unis in 2014, you don’t just get education — you also get re-education, Soviet style.

The censoriousness has reached its nadir in the rise of the ‘safe space’ policy. Loads of student unions have colonised vast swaths of their campuses and declared them ‘safe spaces’ — that is, places where no student should ever be made to feel threatened, unwelcome or belittled, whether by banter, bad thinking or ‘Blurred Lines’. Safety from physical assault is one thing — but safety from words, ideas, Zionists, lads, pop music, Nietzsche? We seem to have nurtured a new generation that believes its self-esteem is more important than everyone else’s liberty.

This is what those censorious Cambridgers meant when they kept saying they have the ‘right to be comfortable’. They weren’t talking about the freedom to lay down on a chaise longue — they meant the right never to be challenged by disturbing ideas or mind-battered by offensiveness. At precisely the time they should be leaping brain-first into the rough and tumble of grown-up, testy discussion, students are cushioning themselves from anything that has the whiff of controversy. We’re witnessing the victory of political correctness by stealth. As the annoying ‘PC gone mad!’ brigade banged on and on about extreme instances of PC — schools banning ‘Baa Baa, Black Sheep’, etc. — nobody seems to have noticed that the key tenets of PC, from the desire to destroy offensive lingo to the urge to re-educate apparently corrupted minds, have been swallowed whole by a new generation. This is a disaster, for it means our universities are becoming breeding grounds of dogmatism. As John Stuart Mill said, if we don’t allow our opinion to be ‘fully, frequently, and fearlessly discussed’, then that opinion will be ‘held as a dead dogma, not a living truth’.

One day, these Stepford students, with their lust to ban, their war on offensive lingo, and their terrifying talk of pre-crime, will be running the country. And then it won’t only be those of us who occasionally have cause to visit a campus who have to suffer their dead dogmas.