Laurence Fox is not a fan of the BBC. Last week, on the very same day that Fox appeared on Question Time, a YouTube video was uploaded featuring the actor in conversation with fellow right-winger James Delingpole. The two men agreed that the BBC was telling people how to think.

“I don’t want my own children being shovelled with rubbish,” said Fox about the broadcaster, on which he would appear later that day. “I would never choose to be indoctrinated.”

Fox’s criticism was oxymoronic. Indoctrination describes the involuntary adoption of beliefs – choice specifically does not come into it. And when it comes to Fox’s political beliefs, there is a fairly strong argument that they have been involuntarily formed. Why? Well, because the actor has described his politicisation in his own words. He is a self-confessed victim of YouTube indoctrination.

Back in November, when Fox was just beginning the promotion cycle for his new album (A Grief Observed, out now), he told the Times that he spent a lot of his free time watching YouTube videos. He said he had been “totally radicalised” by what he had seen and he was setting out on a crusade against woke culture and political correctness.

A month later (and a month deeper into album promo), Fox consented to a quickfire Q&A with the Guardian. He was asked who he would invite to his dream dinner party.

“Jordan Peterson and Cathy Newman: I could just sit back and watch,” he replied in reference to a YouTube video with 18 million views.

Within the canon of YouTube radicalisation, the video Fox was referring to – an interview about political correctness in which the Channel 4 presenter visibly struggles with the Canadian academic’s debating skills – is about as textbook as it comes. Even if you disagree with him, Peterson makes good viewing. He preens, he explicates, he darts, he lectures. It is a barnstorming performance. But there is another reason why the video is so popular: the subtext. An alternative title for the video could quite easily be “The CLEVER Man puts SILLY Woman in her place”. If you don’t believe me, read the never-ending stream of misogynist comments under the video.

YouTube is the second most visited website in the world. It makes money through advertisements. The way that YouTube keeps its audience watching videos is through its recommendation algorithm: every time you finish watching one video, YouTube automatically and seamlessly plays a supposedly related one: encouraging the viewer to waste a succession of hours on Minecraft, make-up, football or politics. British adults now watch an average of 34 minutes of YouTube a day. People between the ages of 18-34 watch almost double that.

I should know. Like Laurence Fox, I used to enjoy watching debates on YouTube. At university, my drug of choice was Christopher Hitchens. It was Hitchens the atheist that I liked – skewering the orthodoxies of the monarchy or the Catholic Church – but I soon found myself recommended videos in which Hitchens’ attacks on intolerance themselves became intolerant (mostly towards Islam and women). Knowing that I also enjoyed watching Roger Federer and Arsenal goalkeepers, and in an effort to keep me watching, YouTube took me to some very strange places. A Swiss backhand might be followed by a mixed doubles video where male tennis players served aggressively at women. My favourite David Seaman save against Sheffield United might be followed by a compilation of errors by women keepers.

What YouTube had discovered was that you could keep people watching – and maximise profits – by recommending increasingly extreme content. This isn't too concerning if the subject matter in question is “Super-Cool Lego Projects”. But when it comes to videos about vaccines or immigration, the consequences of this algorithm are grave. While political broadcasting is subject to strict legislation in the UK, hence the lack of partisan news channels like Fox News, YouTube is not so regulated.

People who have benefitted from this free-for-all include such far-right vloggers as Carl Benjamin (aka Sargon of Akkad) and Paul Joseph Watson. The latter has 1.78 million subscribers – significantly more than the 1.1 million daily circulation of the Daily Mail. Watson’s most viewed video is a conspiracist investigation into the secret messages hidden on the dollar bill.

While much good investigative work that has been done in the UK on the political effect of Twitter and Facebook, surprisingly little has been done on YouTube. A year ago, in a very haphazard way, I researched the most viewed British politicians by name. They were, in order, Boris Johnson, Tommy Robinson and Nigel Farage. It is worth bearing in mind that Theresa May was the prime minister at the time. The attention-seekers, the entertainers and the extremists were winning the online war. A rationalist like Hitchens would surely be appalled.

In the United States, the radicalising effect of YouTube has been doggedly pursued by the likes of the Washington Post and the New York Times as well as numerous academics. Last year YouTube was shamed into tweaking its recommendation algorithm (and also banned Robinson from the platform). Now viewers seem to be nudged towards more reputable sources, but the company remains very secretive about its prized asset.

Which brings us back to the BBC. The problem? Reputable broadcasters are now trying to emulate the success of the beneficiaries of the algorithm – extremist vloggers like Watson. Realising that the best way to gain airtime is to make their content more extreme, they have aped the conspiracy theorists. Take, for example, the clip posted to YouTube of Fox’s Question Time appearance by the BBC: with the incendiary title “Row breaks out over Harry & Meghan royal finances question!” And underneath the video itself, openly racist and sexist remarks proliferate in the comments.

The reactionary politics that spread on YouTube have become worryingly mainstream: Fox’s radicalisation, and the response to his appearance, makes that clear. We should be deeply concerned if constantly escalating content begins to dictate the agenda of other established broadcasters.