I spent most of the last week blocking and muting lunatics on Twitter. I expressed an opinion about Israel that fell disgracefully short of vituperative denunciation, so a horde of social-media vigilantes descended to throw digital ordure on me.

The reason for this roasting was that I’d pointed out that it wasn’t nice of Seth Rogen, a film star who has as many Twitter followers (just over nine million) as there are people in Israel, to join in the online bullying of a Jewish woman called Eve Barlow, who I hadn’t heard of before but who, the algorithm told me, has the temerity to support Israel.

The insults came in waves. First from the American left, then from the American right, because les extrêmes se touchent. The British left turned up on the second day, and a man with “#Antifascist #Antizionist” in his handle sent me a lovely picture of Goebbels. Then the British right joined them, because the Friends of Jeremy keep the strangest company.

On the second day, Seth Rogen bestirred himself from his weed fug and denied he’d done anything, and anyway, my piece had appeared in the Spectator, which is a pro-Nazi publication, man. It seemed like most of Rogen’s followers agreed, but then the cavalry arrived in the form of a couple of Israeli activists. And then their followers turned up, and everyone started screaming at each other.

By this point I was feeling a bit frazzled from pondering screenshots of my Semitically flared nostrils and pictures of dead Arab babies, and it occurred to me I might be able to tiptoe quietly away.

But then the editor of this paper retweeted my original article, and I got a further barrage from an assortment of Islamists, neo-Nazis, flat-earthers and people with inexplicable doubts about Keir Starmer’s integrity.

All of this is completely normal. This is how politics is done in the digital age. The Americans have launched an experiment unprecedented in the history of modern democracy. The public square is now in private hands: the small and ideologically homogenous group of social media companies known as Big Tech.

Big Tech regulates, or fails to regulate, not just political debate but all kinds of information: the contents of Hunter Biden’s laptop, the origins of Covid-19 and, yes, the really important stuff like property disputes in Sheikh Jarrah. If Facebook and Twitter allow incitement against Jews, it’s because clicks are money. The traffic is good for business.

The “legacy” media — newspapers, radio and television — used to pride themselves on “objectivity”. But that was when their business model rested on selling ads. Then Big Tech trashed that model, so now they depend on Big Tech to supply their audiences.

The legacy media survived by dispensing with luxuries like the foreign desk and adopting the digital strategy of outrage and extremity. The rigged digital marketplace did the rest. Add a dose of Trump Derangement Syndrome, which suspended professional ethics in the name of “resistance”, and you have the American media of today.

The slogan of the New York Times is still “all the news that’s fit to print”. The Washington Post still tells us that “democracy dies in darkness”. But they’ll publish anything that will generate clicks from their partisan audiences. Like all rare commodities, the truth is a luxury.

The journalists think they’re political activists. They use their moral commitments in deliberately immoral ways. I’m a big boy, so I really don’t care if people send me rude messages. But we should all care when the New York Times runs casualty reports from the Hamas-run Ministry of Health in Gaza without checking its sources.

The Israeli-Palestinian conflict has become a puppet theatre in America’s culture wars. Unlike in Britain, where most of the media leans right, most American media leans left — and often hard left. The ends justify the means: a blood libel against the Jews is justified as an attack on the Republicans.

Israel will survive the disapproval of the New York Times. But it’s not clear whether liberal democracy can survive in a “post-truth” America. Nor is it clear how American Jews are going to keep their footing when the media has realised that demonising Israel is a smart business strategy. I find this last part puzzling, as thousands of people messaged me on Twitter last week to tell me that the Jews control the media.

Dominic Green is deputy editor of the Spectator’s World edition.