Six years ago, I wrote a column here arguing that Islamophobia was a real thing.

The writer Douglas Murray had said in these pages that it was, in essence, a fabulation and I tried to show — point-by-point — why that was completely wrong.

Last Friday’s massacre in Christchurch was a horrible, practical vindication of that piece.

Fifty worshippers were slaughtered for no other reason than that they were Muslims. It wasn’t their race — they belonged to several. It wasn’t their original nationality, because those, too, were many. The killer’s manifesto was a demented confection of arguments, symbols and prejudices that turned around one central proposition —that Muslims were destroying the West by the very act of existing.

Every symbol and event invoked spoke to the belief in an existential clash between the “civilised” peoples on one side and Muslims on the other.

If that wasn’t Islamophobia — irrational hatred of Muslims as people — what on earth was it? Plenty of Jews didn’t need to be told. For several years now my friends at Tell Mama UK, originally advised by the Community Security Trust, have recorded cases of anti-Muslim bigotry and counselled victims.

The most often repeated expression of this hatred is the woman attacked and ridiculed for wearing a hijab. Not because of the sartorial inclinations of the attacker but because she is a Muslim.

If it walks like a bigot, talks like a bigot, kicks like a bigot it’s usually a bigot. I recall a security camera sequence from Berlin not so long ago in which a man pauses on the steps of a subway when he sees a woman in a headscarf, and then, with one kick in the back, sends her flying down a set of stairs. What was he, then? What would we call it if the victim had been a boy wearing a kippah?

So I have no doubt about this. But what I have noticed is a bizarre form of binary thinking among some Jews and non-Jews alike. It embodies an absurd and dangerous kind of binary thinking, which seems to be that if Muslims are up then Jews must be down. If Islamophobia is being talked about, then antisemitism as an issue must have gone on the back-burner. And — of course — vice versa. It’s a sort of competitive victimhood.

But not all prejudices are the same. Jewish identity has historically been linked to the idea of a Jewish homeland. The achievement of such an ambition is comparatively recent. The same cannot really be said about Muslim identity, which is one reason why an attempt to draw Palestine or Kashmir into a definition of Islamophobia is misguided.

It’s true, too, that some people — Muslims and non-Muslims — have tried to use the accusation of Islamophobia as a way of deflecting criticism of some practices and attitudes that are now widely regarded as outdated or illiberal. I have been a target of this for the last decade or so, and it’s very unpleasant.

But some Jews do this with antisemitism. We all know this and have encountered it. There is a degree of truth in the accusation that the most extreme apologists for Israeli government actions will level the accusation as soon as any trenchant criticism comes Bibi’s way. Yet this in no way justifies the suggestion that antisemitism is therefore not a problem.

So finally we’re left with the suggestion, made at times in these pages by other commentators, that there is something uniquely problematic about the religion of Islam itself, from Bosnia to Indonesia — something that cannot be said about any other religion, be it Christianity or Buddhism. This argument is, ironically, a total surrender to the same argument being made by Muslim fundamentalists about the essential nature of their faith. It is what they, too, want people to believe.

Yet is it is clearly ahistorical. It is a matter of pure fact that in the diaspora Jews often suffered more from Christian oppression than Muslim oppression. What changed is that Christian practices changed. The monolithic semi-theocracies gave way to secular democracies, with the church playing its part. Likewise Judaism developed. And so will and does Islam.

For everyone, not just Jews, the way to assure a future together — and it will be together — is to see our common humanity. Those who take it upon themselves always to stress difference and conflict, almost in fact to enjoy it, are the ones who give most hope to the shooters and the bombers.

David Aaronovitch is a Times columnist