You may not have heard of John Boyne, but you’ll almost certainly have come across his most famous book, The Boy in the Striped Pyjamas. A children’s novel about two boys meeting through the barbed wire of Auschwitz, the book was met with heavy criticism for its historical inaccuracies – none of which stopped it selling a staggering five million copies worldwide and being turned into a Hollywood film. But this week Boyne has been floored by a far tougher foe than a few grumbling historians: he’s incurred the wrath of the gender police.

Boyne’s new book, My Brother’s Name is Jessica, is about a teenage boy who comes out as a trans girl. Aimed at young adults, the novel is narrated by the child’s 12-year old brother, and is designed to be a warm and sympathetic account of what it feels like to grow up transgender. Boyne talked to a number of trans people for his research, and no doubt expected his efforts to be garlanded with praise from a grateful trans community.

If so, he couldn’t have been more wrong. The problems began when Boyne wrote a piece in the Irish Times publicising the book. Mentioning the heated arguments over trans rights (many women are unhappy about government proposals to simplify the process of changing legal sex, feeling it is open to abuse by predatory men), Boyne attacked Father Ted writer Graham Linehan for his apparent obsession with the issue. Linehan, he wrote, 'comes across as someone masking intolerance by promoting himself as a champion of women', adding: 'women can look after themselves just fine… they don’t need a man to do the job for them.'

Perhaps attempting to be even-handed, he went on to criticise trans activists’ attacks on Martina Navratilova, who has argued that trans women have no place in women’s sport, and said he rejected the label 'cis' – a term used to describe everyone who isn’t trans: 'I don’t consider myself a cis man; I consider myself a man.'

Alas for Boyne, trans activists don’t have much truck with even-handedness. A full-on Twitter onslaught ensued, with Boyne hounded for, among other things, defending Navratilova, not liking the term 'cis', 'misgendering' the trans character in the title of his novel and daring to tell Jessica’s story from the point of view of a sibling. 'Boycott @john-boyne and his new "novel" "My Brother’s Name is Jessica" in which his transphobic main character PHYSICALLY ASSAULTS a trans woman and this action is never condemned' was one typically unhinged tweet. Boyne’s literal-minded detractors – almost none of whom will have read the newly-published novel – raged that 'cis' people had no right to tell trans people’s stories in the first place. 'John is not trans therefore this isn’t his story to write' was one typical tweet – an argument that, carried to its logical conclusion, would stop anyone writing a novel about anything other than their own personal experience. Eventually it all became too much, and Boyne deleted his Twitter account.

Has Boyne learnt anything from the experience? Apparently not. He told the Irish Times afterwards that he did not believe that the trans community 'bears any relationship to… the actions of online trolls.'

You could be forgiven for shrugging your shoulders and agreeing with Boyne that this is just another silly Twitter spat. However, the bullying has long since found its way into the real world. As the Spectator’s James Kirkup has pointed out, people who express even mild dissent from the tenets of transgender ideology are being reported to their employer, or visited by a police force eager to act at the behest of this increasingly shrill lobby.

Women wanting to discuss self-identification now have to keep the locations of their meetings secret, because trans activists have targeted venues, in one case with a bomb threat. Before one meeting, a 60-year old woman was physically attacked; at another, masked protesters stood outside hurling abuse. Last month, an Open University conference on prison reform was cancelled after threats from trans activists.

This is no longer just a dispute between feminists and trans activists about a conflict of rights. It is a full-scale assault on free speech. There seems to be no middle way – trans activists will continue with their abuse until all dissent has been silenced. Instead of pandering to their demands, Boyne should do the truly courageous thing and join men like Linehan and Kirkup in speaking out against a vicious campaign of harassment and intimidation.

And you know what? Despite Boyne’s belief that women don’t need men to fight our battles, most of us are very grateful for the handful of men who have had the guts to offer their support.