When voters in Makerfield head to the polls next week, their decision, as is increasingly the case across the nation, may come down to this: whether to be more swayed by a hopeful vision of the UK or by a narrative that defines the country as little more than the most shocking thing they have seen on their phone that day.

That quandary has been sharpened by something that has quietly become a regular fixture of social media: members of the public are now consistently fed a stream of exceptional images and videos that once might have only been seen by investigators or from the inside of a courtroom. It is so regular that it has become banalised, whether it’s of robbers smashing up a jewellery shop, or of extreme and graphic assaults akin to snuff films.

Much of this is broadcast in real time from the phones of bystanders. That includes the horrific footage out of Belfast this week, of a Sudanese refugee alleged to have carried out a knife attack on a white man, gleefully circulated on X by the likes of far-right activist Tommy Robinson. Considerations of the decency of sharing such footage, of how the circulation of graphic, violent crime images can indignify and rob victims of bodily agency, are nullified by what are considered greater political priorities: to identify and profile the ethnic violence that is supposedly tearing the fabric of the nation. And here, the result of an extreme incident of violence was racist riots – droves of meticulously organised masked fascists in Belfast who already had “hitlists” of the homes of migrants and ethnic minorities and set to burn them down.

That knife-attack image is potent. In solidarity protests in Southampton, the scene of riots over Henry Nowak’s murder last week, it is illustrated on banners. It has perfectly landed within a pre-existing online visual language that has, for some time, cast the United Kingdom as in decline, and besieged by “invaders”, with ordinary white people betrayed by the state that was meant to protect and privilege them.

What is that visual language? It can be summarised by the ubiquitous “Yookay” meme, an emblem of urban decline as supposedly accelerated by multiculturalism. It is of selective crime clips posted by far-right accounts and crime news aggregators on X such as @CrimeLdn; AI-generated images of migrant men assaulting white women or replacing iconic British buildings with large mosques; fake videos of young black men in balaclavas, “roadmen”, distributing machetes in the House of Commons – all of this is consolidated by conspiratorial claims of state cover-up, purported images of what the powers that be do not want you to see about the real state of the UK. So what happens when real, but isolated, footage of such crime lands on your feed is that it both feels indistinguishable from, and reaffirms, the slop content and narrative that has already been pushed and established.

Perhaps the mobs in Belfast did not need the direction of online agitators to respond so aggressively to this incident. Nonetheless, politicians of the hard right seize on such images to foment disorder. Where responsible politicians would not so casually circulate such violent imagery, the likes of Reform UK’s Nigel Farage and Restore Britain’s Rupert Lowe say, come, Britain, come and see how you have been betrayed by the state. It echoes the conviction of Enoch Powell, when he said, in 1968, that allowing a growing immigration population “is like watching a nation busily engaged in heaping up its own funeral pyre”.

With a screenshot of the incident, Lowe simply writes, “Millions must go”, while Farage, resharing the image via the rightwing-aligned news aggregator Politics UK (co-owned by a Reform councillor), says “the authorities must reveal the identity and status of the attacker immediately. The public are entitled to the truth” – a truth that, it must follow, is repeatedly being concealed from you. Reform’s spokesperson for home affairs, Zia Yusuf tells you what your eyes must believe: that “the horror of what you have seen in Belfast is a direct result of treacherous Tory and Labour immigration policy” (policy partly overseen, of course, by Reform grandees Robert Jenrick and Suella Braverman, both Conservative ministers in the Home Office when the alleged attacker was granted leave to remain).

The gift of all this is that in an image, a real image, that can allegorise civic decline, the politics comes pre-formed, sustained purely by the existence of the image, with no need to articulate an argument. What the hard right can then provide in response to such distress is blunt-instrument policy: a total ban on visas from anyone from Sudan, says Yusuf; the death penalty returned, says Lowe.

And what of Labour? Its leaders have the much harder job. They can take no victory, or expedient political soundbite, in net migration falling by almost half. People do not live or experience their lives by data and they do not care. In any case, that migration has fallen has only provoked the hard right to reach for more extremes to continue making inroads. You cannot in any sense feel that there are fewer migrants entering the UK, but you can be roused by the image of one among millions committing some atrocious act. You can be promised a more vicious, more ruthless border policy.

Starmer’s national telling-off in response to the Belfast racist rioters targeting people “because of their background” and his appeal for “calm” – even though palpably correct – cannot meet or subdue the angered and visceral response from those who view that image of a black suspect over the stricken body of a white man, and see it as the loss of their dominion. Presented with that image, asked to answer for their defence of diversity, to explicitly and without caveat say that the actions of one attacker cannot sensibly represent entire racial groups becomes impossible for them, even with the most intricate triangulation.

It is hard enough to convince people of unreality; it is harder still to convince them that a singular reality can be unrepresentative. One image of real violence can overwhelm all statistical evidence that violent crime is down year-on-year, across the UK, including in Northern Ireland. It exposes a structural disadvantage that plagues liberal politics. The hard right can simply point to images and tell a straightforward story, however true or false. Liberal politicians must choose between explaining context, embracing social complexity, and fussing over minute statistics, or allowing the hard right to gain ground by deferring to their narrative. Contending that is the difficult task that awaits whoever is to lead Labour into the end of this parliamentary term.

In Makerfield, Andy Burnham quickly jettisoned his previous pro-immigration stances, wagering that the pro-leave constituency would not take kindly to a compassionate policy on recourse to public funds for migrants, which he has advocated as mayor of Greater Manchester. But parroting the “legitimate concerns” mantra is easy. Far harder will be what few senior politicians of the centre-left seem to have developed an answer for, but which becomes all the more pressing in our image-saturated hate economy: how to win against a visual politics, that is in the gift of the right. Burnham, or whoever is to lead our country, will have to find solutions fast.

• Jason Okundaye is a Guardian Opinion assistant editor

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