I made a mistake last week. Irritated by a comment on X/Twitter, I replied to it. The original post had accused Israel of targeting children with drones. I just pointed out that they do not.

This is a fairly limited, and obviously correct, observation. It does not say anything about the conflict overall, nor does it say that children have not been killed. It just says Israel doesn’t target children with drones. Which it doesn’t.

Soon, my comment was picked up by Owen Jones, a left-wing commentator with a large following, who posted: “You have claimed that the Israeli army do not target children, they only target Hamas. These are the last moments of 11 year old Abdullah Hawash. This is the West Bank, which is not ruled by Hamas. How would you describe this exactly?”

I was inundated with comments calling me an atrocity denier, a supporter of genocide and a deluded person unwilling to confront evidence that contradicted my points. A number of them thought I should be in jail. Still others claimed to be creating an archive to which my atrocity denial would be added.

Nearly three million views later and the whole thing was still going. I decided not to comment further. What would have been the point?

It was very frustrating to find that so many people who obviously regard themselves as capable of great military insights and sophisticated understanding of the diplomacy of the Middle East nonetheless don’t understand the meaning of the word “targeting” or the meaning of the word “drones”.

I was therefore, along with the insults, flooded with so-called evidence and talking points that didn’t at all demonstrate that Israel targets children with drones. This article will doubtless inspire more of those.

It was, naturally enough, mildly unpleasant. But only mildly. It is quite irritating to face a barrage of insults from people who appear not to be able to comprehend a simple point, but I took the view that the misunderstanding was more their problem than mine. I wouldn’t want to stop it. Even if I found the obtuseness of some of the points annoying, I can’t say I didn’t learn anything.

Much of what I was sent was of moral and political importance, even if it wasn’t a reply to my point. So, actually, I think it did make the case for free speech on Twitter. Elon Musk, the site’s owner, is convinced that unimpeded debate is constructive and I think this was. Even if it might not appear so and the standard of comprehension was woeful.

But at the same time as being a place for wild and angry political points that are hard to take but of some value, Twitter has now become something else.

It has become a forum for flatly antisemitic conspiracy theories. I don’t mean by this things that could be seen as antisemitic if viewed in an certain unsympathetic light. I mean directly and explicitly antisemitic posting, arguing that Jews are responsible for every sort of evil, from paedophile crime to war of all kinds.

Because we have been understandably vexed at the antisemitism of the left and how Jew hatred has become part of liberal mainstream discourse, we may be missing the way that the American right has turned.

There is now open antisemitism on numerous racist, right- wing accounts with large numbers of followers, taunting Jews and spreading lies about us.

The way Twitter is now run, these accounts are almost impossible to avoid. You no longer only see those accounts you follow.

If you have ever clicked on the posting of an antisemite, you receive streams of antisemitism from other accounts.

Twitter has been a useful source of information and is an important forum for discussion and following political debate. Yet increasingly it is hard for Jews to be on the site because the experience is too awful. This is not because of aggravating and sometimes appalling comments about Israel. It is not because of an unwillingness to listen to alternative opinions.

It is because of the large amount of straightforwardly racist material on the site, which no one appears to be willing to do anything about.

Because of the massive public argument we are engaged in over Israel, we have paid this relatively little attention. But it is a serious and rising problem. Soon we will have to turn to it.

Daniel Finkelstein is associate editor of The Times