Mr Ahmed has the intellectual rigour to see this, and the courage to say so. “I agree ideology is not the only cause and may not be the driving factor,” he writes. “But I don’t see young impressionable Muslims citing they don’t have a job and that is their reason — no, they are going in drives (sic) to join a ‘so called’ religious state that gives them a vehicle and a justification to carry out mass rape and killings including low and behold, FELLOW MUSLIMS! . . . ideology gives them the justification. Unless you remove that you will always give people an avenue.” He pointedly asks if any of the letter’s signatories — who include the organisation Cage, which blamed MI5 for radicalising the British cutthroat Jihadi John — “are doing and Preventing on the ground? . . . Hmmm I wonder.”

But then comes the screeching handbrake turn on Israel-Palestine. In a separate posting Mr Ahmed accuses Netanyahu of “leading his supporters into becoming another Daesh-style state; led and influenced by bigotry and religious illiteracy”. A “Daesh-style state”? Is this the same Waqar Ahmed who takes on the Prevent detractors? Does Israel carry out public beheadings or throw gays off high-rise blocks in Tel Aviv, abandoning its status as the gay capital of the Mediterranean (then stone them if they survive)? Does its edgy film industry, often challenging to the status quo, subvert its talents to choreograph executions by burning Palestinians alive or drowning them in cages, all immortalised with a director’s gimlet eye? The analogy with Daesh is unspeakable.

I have also been told of another Prevent official who showed slides in a training session that appeared to draw an analogy between a Daesh patrol and an Israeli tank.

Shouldn’t someone have a word with this official and Mr Ahmed? Abuses against Palestinians by the IDF and religious extremists there certainly are in Israel. There are also sizeable inequities between Israeli Jews and Israeli Arabs although these are narrowing. The newspaper Haaretz — no friend of the Netanyahu government — reports that relations between the two have improved significantly over the last 15 years. And the stabbings have highlighted a big difference between how Israeli Arabs and the 320,000 Palestinian Arabs in East Jerusalem see Israeli Jews. Unlike their East Jerusalem compatriots, who have not opted for Israeli citizenship, Israeli Arabs have condemned attacks on innocent bystanders.

But IDF abuses (there is no occupying army in the world, including the British, that has not been guilty of them) and extremism in some sections of Israeli society are not representative of the country’s civic society as a whole. In truth, Israel remains the only Middle Eastern country that enshrines values closest to those as defined by the British government’s Prevent strategy: democracy, free speech, a muscular press, an independent judiciary, and pluralism.

I suspect that Messrs Qadir and Ahmed do not agree with the picture I paint of Israel. They are entitled to their view — and to express it publicly in the inflammatory terms that they have, if they must, were it not for the fact that not only are they funded by a government counter-terrorism programme but that what both have written would also be considered by the government as promoting a warped worldview.

That is not, of course, to say that either man intended to incite violence — far from it. But their views aren’t likely to discourage any angry young Muslim already simmering with prejudice either.

But then again, as I discovered while making a programme for BBC Radio 4 on the Channel deradicalisation programme, even some of the senior officials at the heart of Prevent don’t seem to agree with how the government defines extremism.