At a fringe event at Labour Conference on Tuesday, an MP made some insulting remarks about one of her constituents. The 33-year-old man in question served in the army for a decade, rose to the rank of captain, and was deployed to Afghanistan on two occasions. During his distinguished military career, he qualified as a pilot of Apache helicopters and served as the gunner – meaning he operated the helicopter’s weapons as well as flying the craft himself. His MP, based on a story she had partially overheard, wrongly told Labour supporters that he had been unable to pass the flying exams and was too incompetent to play a proper role in the army.

The member is Emma Dent-Coad, newly elected MP for Kensington, and the constituent is Prince Harry.

On the same day, the media went into a frenzy over the judgement given to Lavinia Woodward, a 24-year-old Oxford student who has appeared in court charged with attacking her boyfriend with a knife. The coverage told the story of a violent addict and menace to the public who had been let off prison because a gooey-eyed judge had deemed her too posh, too pretty and too clever for incarceration. Her family’s wealth took centre-stage in almost every report, and the headline “toff-justice” went viral.

The truth wasn’t nearly so sensational. Lavinia Woodward, a girl who had suffered mental health problems since childhood and had become addicted to class A drugs after an abusive relationship, was given a suspended sentence to allow her to “continue with her counselling” and “demonstrate that she could truly rid herself of drugs and alcohol”. The type of sentence the judge conferred is often used in cases in which the defendant has no criminal record, has shown true remorse, is deemed not to be a danger to anyone, and did not commit too grave a crime. Lavinia, whose boyfriend was treated with some anti-bacterial drops and three stitches in his leg, was a prime contender.

Both stories are classic examples of “fake news”, but what’s noteworthy is the blasé reaction of the perpetrators. After Prince Harry’s military credentials were published (proving Dent Coad wrong on every front) the MP admitted she “may have been mistaken”, but said she would not apologise because she was making a “wider point about the Royal family”. In the case of Lavinia Woodward, just one mainstream British media outlet – the New Statesman – made any attempt to set the record straight, and as a result the Twitter abuse has been vitriolic.

There is a dangerous narrative creeping in to mainstream Britain which explains why both Dent Coad and the media knew that they could get away with their behaviour.

It is that those who are privileged and wealthy are so fundamentally bad that the rules don’t apply when it comes to tearing them down. They are not just ignorant or greedy, they are evil – and they deserve everything they get.

This narrative was not written by Jeremy Corbyn and Momentum, but their ascendance has made it ubiquitous. Behind the chants, the t-shirts and the vague talk of love, there is a darker side to the movement. As the slogan makes plain, the noble desire to get justice for the downtrodden is matched by an equal and opposite desire to get revenge on the rich. “For the many, not just the few” or simply “for the many” would both be powerful slogans, but both would only convey half the message. “For the many, not the few” says it all: “the few” are the enemy, and we are against them.

Unsurprisingly, this rhetoric has fuelled class warfare amongst millennials. In my university seminars, it was all too often necessary to preface arguments with “I didn’t go to a private school but”, because anyone who had was dismissed out of hand for not “understanding the real world”. In one of my classes, a quietly spoken guy with mainstream opinions was shouted down by a gaggle of irate students – one of whom yelled that she “wouldn’t listen to him” because she “knew what he really was”.

She was referring to the fact that the death of his father had made him a Peer.

More worryingly, when I asked a neighbour the other day why her son had left Eton before the sixth form, she explained that in his fifth year, a friend of his had been quite seriously injured when a group of locals had started throwing glass bottles at passing Eton boys who had had the temerity to wear their uniform around the town. Apparently, this sort of abuse was a pretty common occurrence – and she was becoming increasingly worried about his safety.

Still more alarming was the hard left’s illuminating response to Grenfell. Before any investigation into culpability had even begun, the “Nobody likes a Tory” Facebook page was gleefully reporting that deputy leader of the council, Rock Feilding-Mellen, had been forced to flee his home with his young family after receiving death threats. A few weeks later, Shadow Chancellor John McDonnell was encouraging people onto the streets for a Day of Rage protest to “get the Tories out” – while Emma Dent Coad, the local MP, pointedly explained that the people of Grenfell were her real constituents, and that she was not in the business of representing “the posh Kensington down the road”.

In the case of Grenfell, this consensus – though not justifiable – is forgivable. It is a genuine cause for righteous fury that an avoidable tragedy like Grenfell could happen in such a wealthy area, and of course, it’s understandable that consideration for the councillors was eclipsed by concern for the victims.

The problem is that the Grenfell response was a symptom of something bigger, and more toxic.

Of course, there are people who deserve our sympathy more than Prince Harry or Lavinia Woodward. They are privileged, and in some respects that means that their lives will be a hell of a lot easier than most. But there is a line between refusing to sympathise with “first world problems”, and denying one sub-section of the population respect, a fair hearing, representation, or truth – the hallmarks of a civilised society.

And if you’re wondering when that line gets crossed, I can tell you: it’s when demonising a mentally ill victim of abuse is socially acceptable – as long as she’s a “toff”.