One man is missing. Of course, it’s good that so many of those responsible for a week of terrifying far-right violence are facing an especially swift and severe form of justice – but there’s one extremely rich and powerful suspect who should join them in the dock. If the UK authorities truly want to hold accountable all those who unleashed riots and pogroms in Britain, they need to go after Elon Musk.

To be sure, direct guilt belongs to the culprits on the ground, those currently being fast-tracked in their hundreds through a usually glacial court system – moving from arrest to charges, trial, conviction and (heavy) sentencing in a matter of days. Guilt belongs to those who surrounded hotels housing migrants and refugees, attempting to set them on fire and threatening to kill those inside. It belongs to those who saw fit to trash and loot not only shops, but also libraries and advice centres, many of them lifelines for those who have next to nothing. It belongs to those who smashed and threatened mosques, terrifying those within and whole Muslim communities beyond with a kind of menace many will have heard about in stories passed down from parents or grandparents, but which they will have hoped belonged to a long ago past.

And yet, consider how all this happened. It began as it always begins, with a lie – in this case, the lie that the wicked stabbing attack on a children’s dance party in Southport, which left three little girls dead, was the work of a Muslim migrant who had come to Britain on a small boat. I say “always” because this kind of lie has been told for the best part of a thousand years.

In 1144, it wasn’t Southport but Norwich, and the victim was a 12-year-old boy called William. When he was found dead, the accusing finger pointed instantly – and falsely – at the city’s Jews. Over the centuries that followed, the defamatory charge of child murder – the blood libel – would be hurled against Jews repeatedly, often as the prelude to massacre.

There are differences, of course, starting with the fact that, so far and thankfully, these riots have not killed anyone – although given the attempts to burn down buildings with people inside, that seems more a matter of luck than mercy. But the common element in events nearly a millennium apart is that lies can wreak havoc when they spread. And that spreading now takes seconds.

News of the murders in Southport had barely broken when that false claim about the alleged killer’s identity began coursing through the veins of the internet, advancing virally across social media. It was not organised by one of the official groups of the far right, which remain tiny and fragmented. Nor is there much evidence that it was directed by a malign state actor, with a shadowy facility in St Petersburg pulling the strings. Its method, and that is the wrong word, was different – and much more effective.

“This was individuals, acting individually and anonymously,” says Joe Mulhall of Hope Not Hate, which has long monitored the far right. All of them were doing their own thing, but the overall result was collective movement in one direction, “like a school of fish”.

What gave the phenomenon scale were the “super-sharers”, big-name figures with large online followings who act as “nodes” for the dissemination of lies. Witness the role of Stephen Yaxley-Lennon, who styles himself Tommy Robinson, and Andrew Tate, both of whom amplified the initial bogus claim. Thanks to them, it was seen by millions. As Mulhall notes, these are people capable of making the weather: “One individual can create a mass panic.”

It has become a habit to speak of social media generically, but the core of the problem is more specific. It’s X (previously Twitter). That’s where “Robinson” has nearly a million followers. When he was banned from X and other mainstream platforms, he had to make do with the likes of Telegram, where his reach was more limited. “He was in the wilderness,” says Mulhall. Now that he’s back on X, he can find his way into the phones of tens or even hundreds of millions of people at a stroke. And what happens online carries over into the real world, as we saw at the end of last month, when Robinson addressed a crowd estimated to be in the tens of thousands at Trafalgar Square – and saw again this week.

Let’s remind ourselves who brought Robinson and a whole slew of far-right agitators back in from the cold, thereby putting X out of step with the likes of YouTube and Facebook. It was Musk, of course. He decided to make X a safe space for racism and hate almost as soon as he bought it. The effect was instant. One analysis of tweets found a “nearly 500% increase in use of the N-word in the 12-hour window immediately following the shift of ownership to Musk”. The same study also found that posts including “the word ‘Jew’ had increased fivefold since before the ownership transfer”, and something tells me those tweets weren’t tributes to the comic style of Mel Brooks.

But Musk has not just ushered in the super-sharers of the far right: he is one himself. It was he, on his own X account, who shared with his 193m followers a fake Telegraph headline, falsely claiming that Keir Starmer planned to create “detainment camps” for rioters in the Falkland Islands, and doing it by quote-tweeting the co-leader of the ultra far-right Britain First organisation. It was Musk who inflamed an already incendiary situation by tweeting of the UK, “Civil war is inevitable”.

What’s the answer to this problem? Ideally, all politicians, journalists and influencers would defect en masse from X and use somewhere else as the global exchange for instant news and opinion. So far that’s presented a collective action problem: even governments who loathe X don’t want to leave while it remains a central forum.

It’s clear that schools should be teaching information hygiene, so children learn to avoid fake news the way they would avoid poisonous food. Clear, too, that we need online safety legislation with teeth and if, as Sadiq Khan has suggested, that means toughening up laws so new they are yet to be fully implemented, so be it. I like the idea of fines for social-media companies that don’t honour their own declared standards, though many are so rich they won’t feel it: better to fine the directors of those companies, hitting them in their own pockets. And, as Lies That Kill, a timely new book by Elaine Kamarck and Darrell West argues, given that this is a global problem, it will require a global solution: which “means that countries need to negotiate with each other on ways to cooperate in the fight against disinformation”. If 2025 sees Starmer sit down with a President Kamala Harris, this should be one of the first items on the agenda.

For now, though, there needs to be clarity on the nature of the problem. Lies can indeed kill and, though there are of course many others, one of the world’s most prolific enemies of truth is Elon Musk. He is surely the global far right’s most significant figure, and he holds the world’s largest megaphone. As he may put it, a battle to defeat him is now inevitable – and it has to be won.

• Jonathan Freedland is a Guardian columnist

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