Nell Minow, an American film critic, recently described how in 2010 she had interviewed the Friends actor David Schwimmer. When the noise in the restaurant grew too loud, he asked her whether she might like to move to a room upstairs with him, and if so, would she like a chaperone present. She praised him for this behaviour. ‘He understood what it is like to have to be constantly on the alert and he wanted to make sure I understood I was safe.’

When I read Minow’s story, my reaction was to think what a patronising arse Schwimmer must be. A woman journalist shouldn’t need a chaperone when she is doing her job. But, in the fallout from the Harvey Weinstein allegations, it has become clear that, for many women, safety is starting to trump liberty. We are moving towards a chaperone culture, in which women, delicate lambs that we are, must be protected at all times.

A new schism is opening up between men and women. Women are incessantly told to be vigilant of predatory men and are increasingly scared to be out in public. Men, meanwhile, are becoming more nervous around women for fear that their very nature is itself threatening to the opposite sex. The wrong words, gestures or body language might now render them guilty of one of the new crimes popping up on social media — for example, ‘creeping’ on someone or being ‘too handsy’. The spotlight is on Hollywood and Westminster — or ‘Pestminster’, as it has been dubbed — but it will soon turn to other industries. More sex pests will be exposed or their peccadillos gossiped about on WhatsApp groups. The internet jury will then make its decision.

It’s not hard to see why this is happening. There have always been rapists and men who exploit women for kicks, and the sexual revolution of the 1960s has done nothing to stop them; worse, perhaps, it has given them licence to operate without the old boundaries. We live in a time that is almost defined by seedy characters such as Donald Trump and Weinstein, so it’s natural that women feel they must be on their guard.

Sexual abuse allegations are coming thick and fast. If real crimes are uncovered because women feel emboldened to come forward, that can only be good. It should go without saying that any woman who has been the victim of sexual abuse deserves sympathy and to be believed. Unfortunately, that still has to be said, because too many women are not believed when they tell their stories. And if they took a while to speak, they are doubted because of the delay or told not to cause trouble. Just this week, activist Bex Bailey claimed that she was raped by a senior Labour official six years ago — but was advised by a party official not to report it in case it damaged her career.

But if you look beyond the current hysteria, something sinister is happening. Barriers between men and women that had been knocked down by feminists are being resurrected — in the name of feminism. Whereas it used to be religious groups that enforced sexual morality, in our modern, secular culture, the loudest voices on the internet are taking over that responsibility.

Think of it as a new sexual reformation. Five hundred years ago, Luther posted his 95 theses on the door at Wittenberg; today, prominent women have begun issuing edicts about appropriate male behaviour. Like Luther, these women think it is their mission to change the world.

Earlier this month, the writer Helen Rosner published a guide to ‘20 things men can do to support women, beyond just literally ceasing to sexually harass us’. It included suggestions for men such as ‘seek out women to be your heroes’, ‘talk less. At all times’ and consume ‘ethical’ porn made by women, queer people and people of colour. I wonder what Luther would have made of that.

A lot of this boils down to that boring ancient impulse to separate men and women. There is political chatter about the possibility of ‘women-only carriages’ on trains. The orthodoxy of ‘safe spaces’ —which began as part of the women’s movement before becoming a university campus cliché — is starting to infiltrate public life.

Last year, a survey showed that 70 per cent of British women have taken steps to guard themselves against harassment. The poll included ten different strategies those polled had used, including avoiding parks or public transport, missing school or work or taking a chaperone. ‘Modesty wear’ — clothing which offers an alternative fashion for those who want to cover up — is becoming more popular on the catwalks. In February, more than 40 designers took part in the first ‘London modest fashion week’.

The old feminist trope says that it is not a woman’s responsibility to worry about her own safety; it is a man’s job not to harass her. Yet women are clearly taking increasingly extreme measures to protect themselves because a small number of vocal campaigners are telling us that all our worst fears about men are true — and we must take action. And if this means reinstating old-fashioned segregation at the expense of hard-won freedoms, so be it.

The #MeToo hashtag, which trended on social media in the days after the Weinstein story broke, revealed just how many women considered themselves victims of sexual abuse. But also, how alarmingly wide that definition ran. On my own Facebook feed, the experiences described stretched from rape to ‘feeling as if a man once looked through me’. The implicit message of all these confessional posts was clear: if it hasn’t happened to you yet, you’ve just been lucky. Or perhaps you are in denial. It’s as if a new feminist movement is advocating victimhood, rather than equality. And women who protest about this new reality are denounced as traitors to their sex.

The paranoia isn’t confined to women. Understandably, plenty of men are starting to feel anxious about what this might all mean. Each day brings fresh stories in the newspapers of prominent figures tumbling from positions of power because of a major — or minor — misdemeanour. A sexual abuse accusation, or even a snifter of gossip published online, has the power to sabotage a career and ruin a life.

So men are also starting to think about how best to defend themselves. Nobody wants to be daubed with the pervert brush. Older men tell me that they are nervous that something in the distant past that would once have been dismissed as silly behaviour will now be dredged up as damning evidence. Younger men, meanwhile, seem even more reticent about approaching women or making a move. I heard a story recently about a woman who had been on a date with a man who was younger than her. After a few drinks, they ended up back at her house. The woman was keen to go to bed with him, but he refused because he was so worried about doing something that might later lead to recriminations. In the current climate, who can blame him?

Professional life is becoming a nightmare. Young women feel uneasy about the lay of the land. What career can you choose that won’t involve creeps? And men in positions of authority will inevitably become more anxious about hiring women. It must just seem easier to hire other men, who are less likely to interpret a clumsy comment as sexual assault. Across a wide range of industries, men are being given guidance as to how they should behave so as to avoid getting caught out by this new sexual counter-revolution. Consent classes have been compulsory at British universities for a few years, but law firms and banks are also starting to introduce them. In the military, some officers have been advised that they should ask for a woman to give them consent, filmed on their phone, before taking things further.

It’s a surprise, really, that anyone is having sex these days, given the reputational risk involved. One single girlfriend tells me she is worried about what this all means for her hopes of finding a husband. What sensible man would try it on after a few drinks? Then again, what happy romantic relationship didn’t start with a lunge? Sexual relations are never black and white.

The paradox is that all this paranoia comes during an era of intense sexual libertinism — the decade of Fifty Shades of Grey, one of the bestselling books of all time. We live in an age of chemsex parties and ‘hi-tech sex toys’. Hard-core porn is always a few clicks away. It’s never been easier to hook up, via dating apps or the internet. While embracing so much freedom, society is moving towards prudishness. We all talk about sex all the time, but the safest sex is no sex at all.

This new sexual reformation may leave women feeling safer in a domestic environment, surrounded by other women — or chaperoned when out in public. So what started off as an attempt to give support to abused women mutates into a movement that undoes everything women’s rights campaigners have fought for. Men, too, may cut themselves off, retreating into the company of other men, and we will be back where we were a century ago. How’s that for a sexual revolution?

In the military, some officers have been advised that they should film a woman giving consent on their phone