We watched with agony as another American synagogue was attacked by an antisemitic terrorist, and we shared in the relief when the hostages escaped without injury. But while the BBC and other news networks swallowed the absurd — and now retracted — FBI assertion that Malik Faisal Akram’s attack was “not specifically related to the Jewish community,” we know better.

Here was an Islamist terrorist who targeted a synagogue because he believed that Jews control the US justice system and other levers of power, and wanted to speak to the “chief rabbi of America” in order to secure the release of another antisemitic terrorist, Aafia Siddiqui, who is currently serving an 86-year prison sentence in Texas.

The incident illustrates once again the real-world consequences of antisemitic conspiracy theories, and demonstrates the importance of convicting those who propagate these racist myths and incite others to give violent expression to their anti-Jewish hatred.

Tahra Ahmed, who was convicted of inciting racial hatred against Jews just one day before the hostage crisis, is exactly such a person. As you read about her, I would like you to imagine the impact her lies might have on someone like Akram.

Ms Ahmed, a 51-year-old prominent Grenfell Tower volunteer aid worker, was exposed as having posted claims on social media that the victims of the Grenfell Tower fire were “burnt alive in a Jewish sacrifice.” These posts, originally uncovered by The Times and buttressed by further revelations of her online activity by Campaign Against Antisemitism, were published for tens of thousands to read on Facebook.

Campaign Against Antisemitism, CST and others reported her to police but, despite excellent police work, it took three years to see her convicted due to the dangerous sloth of the Crown Prosecution Service. Yet again, we at Campaign Against Antisemitism had to consider private prosecution and constantly push for progress.

Among the conspiracy theories she promoted online — and on the stand during the trial — were that Grenfell was “owned by a private Jewish property developer just like the twin towers. I wonder how much Goldman [Sachs] is standing to make in the world’s most expensive real estate location [Kensington].” Asked at the trial whether the Jews were to blame for the fire, she said that she did think that, “just like they bombed Gaza every couple of years.” 

She described the Holocaust as the “holohoax”, denied that millions of Jews were murdered by the Nazis and claimed that “Hitler and the Germans were the victims of the Jewish conspiracy to destroy Germany.” She believes too that the 9/11 terror attacks were faked by Jews, and wrote in yet another post: “All the leadership of ISIS is directly recruited by CIA and the leadership are all Arab Jews, trained by Mossad.” We also uncovered posts claiming “Jews have always been the ones behind ritual torture, crucifixion and murder of children,” a comment redolent of the blood libel that she claimed on the stand was “to atone and be let back in Palestine.” Other posts complained about the “hold of Jewish power over our so-called free and democratic society” and referenced “Rothschilds”, “Satanic ruling Jews” and “ZioNazis”. 

The mask of this extremist, whose lawyer described her as part of the “social justice movement”, continued to slip as she posited that “the Talmud talks about sacrificing children” and complained of “powerful people behind world governments.” This toxic mix of far-left, far-right and Islamist tropes, which I exhibited in my witness statement in court, underscore the potency of a venomous worldview that blames the Jews for every perceived evil.

Ms Ahmed discussed her beliefs with some of the people she was helping in the aftermath of the fire. Those people, as the prosecutor observed, were vulnerable and understandably looking for someone to blame. Ms Ahmed purposefully sought to point their fingers at the Jews.

This poison is potent. It begins online but ends in a Texas synagogue.

I am proud and relieved that Ms Ahmed was found guilty by an Old Bailey jury on two counts of incitement to racial hatred. The offence carries a maximum sentence of seven years’ imprisonment. She will be sentenced on 11 February.

Gideon Falter is Chief Executive of Campaign Against Antisemitism