Quite the worst moment during the Brexit campaign was when Jo Cox MP, a mother of two young children, was murdered in the street by a man named Thomas Mair.

Mair has now been tried and sentenced to life imprisonment. We don’t know precisely what his motives were because he refused to speak – or even enter a plea – during the trial. What we do know is that he was a loner with OCD; he kept an extensive collection of Nazi literature in a shrine bookcase; he subscribed to neo-Nazi magazines and ordered books from the National Alliance, the US neo-Nazi group that inspired Oklahoma City bomber Timothy McVeigh; he kept extensive cuttings on Norwegian far-right mass murderer Anders Breivik; he compiled a dossier on Jo Cox, to whose pro-EU leanings he clearly objected; also we know that according to several reports at the time of the death – subsequently disputed – he is said to have shouted as he stabbed and shot Jo Cox “Britain First, this is for Britain.”

You might think, as I do, that here was the case of a bitter, angry, emotionally damaged loner with neo-Nazi sympathies doing what bitter, angry, emotionally damaged loners with neo-Nazi sympathies sometimes (perhaps once every four or five years) will.

But London Times columnist David Aaronovitch thinks he has a much better handle on this awful event. Apparently, deep down, it was the fault of all those ghastly people who voted Brexit. Oh, and by extension, the sort of people who voted for Donald Trump…

Here’s how I summarised his article in a Tweet this morning:

“Everyone to the right of me is basically a dangerous extremist” https://t.co/NlQI5nsySo — James Delingpole (@JamesDelingpole) November 24, 2016

Aaronovitch didn’t like it. He doubled-down with a passive aggressive Tweet to the effect that while I may once have been a nice chap I had now gone to the dark side and become some kind of deranged fascist apologist (presumably as a result of my associations with evil, sinister, post-truth, fake news (TM) site Breitbart).

@JamesDelingpole An irony is that the moment after you tweeted that I started getting tweets from far-right crazies. You used to be fun, J. — David Aaronovitch (@DAaronovitch) November 24, 2016

I asked whether he’d mind sharing all these tweets he’d had from “far-right crazies”. So far, he hasn’t obliged which leads me to suspect that David Aaronovitch’s definition of “far-right crazies” is “anyone who criticises me.”

That lofty, more-in-sorrow-than-in-anger, passive aggression is part of Aaronovitch’s schtick. Since his Oxford days as a Communist-sympathising student union leader, Aaronovitch has matured into a pillar of the Establishment – for years a well-respected Times columnist, author and broadcaster; still on the left, of course, but apparently on the measured, reasonable, grave-and-considered-pronouncements end of the socialist spectrum.

Which, of course, is what renders his commentary so insidiously toxic.

If these were the words of just some rent-a-gob tabloid trot in the Daily Mirror or the Socialist Worker, you could just go: “Bonkers lefties. Don’t you just love ’em?”.

But Aaronovitch thinks he’s better than that. He writes with gravitas and apparent moderation; with what Milton called “words clothed in reason’s garb.”

He doesn’t sock you, as a less sophisticated brand of Trotskyite agitator might, with a “Everyone who voted Brexit is a fascist and they’ve got Jo Cox’s blood on their hands.”

Instead he gets there sinuously and subtly, gently luring the unwitting reader into accepting his dishonest, weaselly assumptions.

One of these false assumptions concerns the way Brexiteers behaved in the immediate aftermath of Jo Cox’s death.

He begins his piece:

In the aftermath of Jo Cox’s murder last June a dismal row broke out on social media. According to early witness reports, her attacker had shouted “Britain first” or something like it several times as he set about killing her with an improvised gun and seven-inch blade. Almost at once perfectly respectable people started arguing that the sources for this claim were unreliable and that her death was being exploited by leftwingers determined to tar the Leave campaign by association with a murderer.

Then he goes on to analyse this reaction:

Why had some people — all of them pro-Brexit as it happens — been so keen to dismiss the first (and accurate) reports of Mair’s words? Perhaps they were worried that his nationalist motives might be exploited to provoke a Remain backlash when Britain voted in the EU referendum a week later. But I don’t think that was the real reason. They resisted because deep down they feared that aspects of the language or direction of the Brexit campaign they legitimately supported had emboldened extremism. While they themselves were in no way permissive of the act, might they in some way have been permissive of the motive? Or even of the mood?

That final paragraph is pure, poisonous projection.

Like most Brexit campaigners, I remember exactly how I felt when Jo Cox was killed: horror at what had happened and sympathy for her family; and also, yes, most definitely, an intense burning hatred of the man who’d done it, combined with a gnawing fear that this random loon had gone and destroyed the hopes of over half a nation.

“How dare you! How bloody dare you!” I remember thinking, when the rumours began surfacing that he’d done it in the name of Brexit, thus utterly misrepresenting the values and motives of all the millions of decent, peaceful people who, for any number of perfectly respectable reasons just didn’t want to be shackled to the EU any more. If we could have done, I think some of us would quite happily have lynched the bastard.

A few hours after it happened, a Swiss journalist friend emailed me to say: “You cannot win this referendum now.”

I feared he was right. So, apparently did Boris Johnson. According to All Out War – Tim Shipman’s book on the EU Referendum – Boris Johnson said: “We’re fucked. We’re totally fucked.”

Yes, you may argue with hindsight that it was unethical for anyone to view an innocent mother’s murder through the filter of their desires for Brexit.

But then, it worked both ways. There were strong suspicions in the Leave camp, at the time, that the Remain camp was cynically exploiting Jo Cox’s murder to blacken their opponents’ motives. Some of the remarks Stronger In’s Will Straw made at the time to his volunteers seemed a mite dodgy: “We need to recognise that people have been pulled up short by Jo Cox’s death. It is now time to make a very positive case for why we want to be in the European Union” and “to call out the other side for what they have done to stir division and resentment in the UK.”

Not-so-subtle attempts were made by Remain sympathisers to link Jo Cox’s murder with an “inflammatory” poster which Nigel Farage had coincidentally unveiled a few hours before her death – the one showing a long stream of migrants under the slogan “Breaking Point”.

As it turned out, Jo Cox’s made little difference either way. What focus groups did show, however – according to Shipman’s book – is that Brexit voters very much resented the idea of being tarred with the same brush as a murderous far-right loon.

According to Vote Leave’s Henry de Zoete, after a focus group the day after Jo Cox’s death: “Normal people think this is just a crazy mad guy, it has nothing to do with the campaign – and if anyone tries to make it about the referendum it’s going to help us.”

Note, David Aaronovitch: Leave voters were NOT going “ooh dear, maybe our dangerous rhetoric was responsible for creating Thomas Mair.” That, my old mucker, is totally YOUR warped projection. Few real Brexit voter, I suspect, actually thought this way – because why would they?

Anyway, I’ve given this piece a headline which I know that Aaronovitch will hate. He’ll think it unfairly misrepresents his article, which – I’m sure in his imagination, at least – doesn’t go nearly so far as to accuse Brexit voters and Trump voters of being tacitly responsible for the random neo-Nazi murderers who (very) occasionally kill people like poor Jo Cox.

But I’m afraid it does. It’s exactly what it does.

Here’s Aaronovitch’s conclusion:

Where does that leave us in trying to draw lessons from this tragedy? It’s a truism that the economic crisis brought to an end the long boom, shook confidence in the democratic system and helped create a playground for anti-establishment forces to run about in. It’s also true that in this atmosphere it has been easy to equate unwanted change with the advent of the alien “other” — migrants, mostly — who become the most visible symbol of a threatening world. But how does this turn into something like Thomas Mair? How does it lead to a horrid uptick in violent abuse and organised neo-Nazi groups? It seems to me that we have to watch out for people who take literally what other people may mean metaphorically. When a Trump says a voting system is “rigged”, journalists are liars or that he wants to build a wall, he may not mean there’s electoral fraud, and he may just mean that papers are biased, or that borders should be better policed. But those who do take these statements literally may, at the extreme fringe, feel themselves to be warriors charged with fighting a literal war. So it matters when a major public figure appears to endorse conspiracy theories which, at their heart, demand violent opposition to legions of imagined plotters. It matters when a British newspaper uses the term “enemies of the people” of the independent judiciary, rather than just saying “Why their lordships are wrong”. What, if you are a literalist, do you do with an enemy of the people? It matters when a British political party (Ukip in this case) consorts with groups abroad who, until a decade or so ago, were wearing Nazi uniforms. There is a spectrum in politics and one part nudges or pulls another. At the far end are people who, by our actions and words, we can bring in or push out. If that’s true of Muslim communities and their handling of Islamist radicals, it’s true of the political right and their own far edges. And it’s time they took responsibility.

What Aaronovitch is doing here in his elegantly disingenuous way is something that we’re going to see the voices of the liberal-left doing an awful lot of in the coming years, as they attempt to come to terms with the fact that they have lost the political argument and that the tide of history is against them.

We’re seeing it in the desperate rearguard actions being fought to frustrate Brexit by the Remain establishment elite (of which of course Aaronovitch is a paid up member, as is the Times which campaigned for Britain to stay in the EU).

We’re seeing it in this bizarre narrative about “fake news” (I mean to write about this in more detail on another occasion) which liberals in the US are asking us, apparently straightfaced, to believe is the main reason voters were deluded into electing Donald Trump as the president of the USA.

“If you didn’t vote Remain and you didn’t vote Hillary, then basically you’re a neo-Nazi” is basically what they’re telling us.

And still they wonder what it was that made us so angry that we wanted to destroy the pillars of their temple of liberal elite smugness – and bring the whole edifice crashing down.