If I were an Israeli, I would be on the streets marching against Netanyahu and his far-right government. Before I write anything about today’s conflict, I try to put myself in the position of a citizen of Gaza whose home is in ruins and family is dead. Obviously, I do not believe that it is antisemitic to oppose the Israeli government.

For all that, it strikes me as incontrovertible that mainstream society is refusing to see the ugliness of the pro-Gaza movement.

The majority of people who go on demonstrations, including people I know and admire, want peace. Their Islamist and far-left leaders, however, want an anti-colonial and anti-Jew war to the death.

Their stupidity is striking for it is a war that only Israel can win. Israel has the military power, and you only need look at the destruction of Gaza and the killings of Palestinians on the West Bank to know that it will use it.

Their bloodlust ought to be equally obvious.

Dave Rich, Head of Policy at the Community Security Trust, has an updated edition out in a couple of days of his cooly devastating account of modern racism, Everyday Hate: How Antisemitism is Built into Our World. It ought to be mandatory reading for anyone who believes that the protests against Israel are uncomplicated.

Rich examines a question of timing that mainstream commentators have yet to notice. As soon as the news of Hamas massacres on October 7 broke, there was an outbreak of nihilistic delight. The murders, the rapes, the burnings alive were “a moment of unparalleled joy and celebration”, said the British branch of the Islamist group Hizb ut-Tahrir. The Palestine Solidarity Campaign organised marches in London, Brighton and Manchester with banners proclaiming “Glory to the Palestinian Freedom Fighters”.

One might have predicted the Muslim revolt against the Labour Party in last week’s elections by the reaction to October 7 in hardline mosques. They echoed to cries of “God rid us of the Jews, the usurpers, oppressors and aggressors”.

It is one thing opposing Netanyahu. It is another to, in Rich’s words, join with people who “looked at the massacres of entire Israeli families, who saw the wanton murder and rape of young festival-goers, who heard about the kidnapping of tiny children as hostages, and called for more of the same”.

Remember, no Israeli soldier had yet entered Gaza. You couldn’t demand a ceasefire because there was no fighting. And yet it was at this point that Rich’s Community Security Trust saw reports of antisemitic hate crime explode in the UK and around the world.

Respectable opinion holds that antisemitism can be a regrettable but understandable reaction to Israeli crimes. Yet there had been no Israeli crimes. Images of Palestinian suffering had not filled our TV screens.

Instead, the harassment and abuse of Jews began as soon as news spread that Hamas had attacked Israel.

The intensity of the reaction needs explaining as well at its suspicious timing. No other conflict can get hundreds of thousands on to the streets week after week. It is not whataboutery to point out that even Assad’s massacres of hundreds of thousands of Sunni Muslims inspired just a tepid response.

Indeed, politicians such as George Galloway, who acclaimed Assad, and Jeremy Corbyn, who worked for Assad’s backers in Iran, are leaders of the anti-Israel movement and no one on the left calls them out.

You can explain the ferocity of the passion by saying that Israel is a democracy and we rightly hold democracies to high standards.

You might say that Britain and the US support Israel, so demonstrations could change government policy. It’s a reasonable argument. But then the UK and the US support Saudi Arabia and you never see tens of thousands protesting against the oppressions of the Saudi monarchy.

The deep history of Christian prejudice and fascism must play a part. The stereotype of the evil Jews who crucified Christ, murdered children and poisoned wells has never died. Indeed, the old blood libels live on in the posters at the anti-Israel protests and help to explain why so many people are relatively unmoved by appalling suffering anywhere else on Earth, yet treat the killing of Palestinians as the greatest of crimes.

Rich develops a novel theory that the very sight of Jews fighting back stirs primal fears. Throughout Christian history Jews were powerless. Sometimes, under both Christian and indeed Islamic rule, Jews were even forbidden from carrying weapons. The Hamas attack on Israel imitated medieval massacres, Russian pogroms and Nazi mass murders of Jews who were largely defenceless.

But in an affront to tradition Jews are armed now and have a state that can fight back with great brutality. This inversion of the old order in which Jews could always be killed disconcerts people at a subliminal level.

I can accept that. But whatever the causes of the joyous reaction to Hamas’s crimes or the mass mobilisations against Israel, I see darkness ahead. My friends who go on the demos believe that they can help prevent the war escalating. I hope they are right. But the ferocity of the rhetoric presages a violent, terrorist future in the UK. I am frankly amazed that it is not already upon us.