So who is this shadow chancellor who has just re-firebranded himself?

John Mcdonnell: voice of reason. As rebrands go, it’s somewhat on the ambitious side. It’s like Darth Vader relaunching himself as a wellness coach, or Herod opening a creche. But there’s no getting away from it. Jeremy Corbyn’s oldest political ally is attempting a radical, and wildly improbable, change of image. In short: he’s trying to go from firebrand to favourite uncle. From grizzly bear to teddy bear.

Yesterday the shadow chancellor was interviewed on BBC Two’s new current affairs programme, Politics Live. At least, we were told it was the shadow chancellor. It certainly looked like him. But it didn’t sound like him.

Whoever it was on screen, it surely couldn’t be the man who once called for IRA terrorists to be honoured for their “bombs and bullets and sacrifice”. The man who demanded insurrection in the streets to bring down the Coalition government. The man who hailed rioting, windowsmashing students as “the best of our movement”. The man who joked about lynching Esther Mcvey MP, and kneecapping Labour councillors for boycotting a meeting with Sinn Fein.

No, that must have been a different John Mcdonnell. This John Mcdonnell was calm, gentle, and unfailingly courteous. His voice was soothing, his frown earnest. Under criticism from the show’s other guests (a mixture of political types and journalists), he didn’t snap, lose his temper or criticise them back. Instead, he looked faintly sorrowful, as if it pained him to think that he might, in some small way, have disappointed these poor, dear people, and longed for nothing more than to make it up to them.

On the Labour anti-semitism scandal he was the very picture of contrition. “This has been a learning experience for me,” he murmured, humbly. “We’ve all got to learn… We’ve all got to have a bit of humility… Sometimes you need to take time to listen, you know…” He said he opposed the deselection of anti-corbyn Labour MPS (“The vast majority just want to get on with the job”). He promised that business had nothing to fear from him (“We’re listening to people, we’re building consensus”). He even praised Theresa May, for her approach to Russia (“She’s doing the right thing”).

Watching him was quite an experience. All these soft-spoken little sermons about learning and listening and humility, the need for peace and unity and togetherness. Never mind chancellor of the exchequer, he sounded as if he were auditioning to be the Dalai Lama.

Will viewers have found this unlikely transformation believable? Well, I suppose everyone deserves a chance to grow, to mature, to put their youthful follies behind them. So perhaps we should give him the benefit of the doubt. After all, when he joked about Esther Mcvey, he was but a whippersnapper of 63.

Today, he’s a changed man. Next time a mob of Left-wing rioters decide to smash some windows, he’ll urge them to do it gently.