The speed and violence of the Tory party’s self-destruction is a remarkable spectacle. Outsiders can only look on dumbfounded as one lot of state-shrinking austerians tear apart the other lot despite identical instincts — except on Europe. This is reformation versus counter-reformation in its ferocity. When the referendum is over, expect a bloody auto-da-fe against the losers. There can be no forgiveness.

Who would expect in their Euro-delirium that the Brexiteers would tear down the entire edifice of their party’s sacred beliefs and policies, as feral as Daesh (the self-proclaimed Islamic State of Iraq and the Levant) blowing up Palmyra?

But there they go, one by one, the arches of Cameron/Osborne conservativism. Most astonishing was Iain Duncan Smith ‘s revelation that everything he has done since 2010 has been “deeply unfair”, taking money from the poor and the disabled to reward the rich.

His own bedroom tax, the £30 billion (Dh156.57 billion) cut from the poorest — all that is thrown back like a boomerang at his pro-EU leaders.

Brexiteer Graham Brady, chair of his party’s 1922 committee, uproots the entire school academisation policy to hurl at pro-EU leaders.

Anti-EU culture secretary John Whittingdale chucks the national living wage back in the chancellor’s face. Even the NHS has been weaponized for this civil war.

Priti Patel ‘s claim that due to EU membership “the NHS is creaking under the strain” of migration and that the “£350 million a week” we send to Brussels is “money that could be better invested in helping patients” was astounding.

This is the Thatcherite Free Enterprise Group minister who co-authored Britannia Unchained, who said that “the British are among the worst idlers in the world” and warned against “the siren voices of statists”.

But in aid of Brexit, she is suddenly eager to pour more money into the idle and statist NHS.

As for Boris Johnson, writing in Monday’s Telegraph he weeps for the steelworkers of Port Talbot.

“Their fate seems so unjust. This disaster isn’t their fault.”

Whose is it? The EU’s, of course — and the leaders of his party who support it. Written with a new seriousness, devoid of his usual Billy Bunter whimsy, he turns the truth on its head.

“The Wales plant has been overwhelmed by a series of misfortunes ... over which these workers might reasonably expect their elected government to have some control, but which the UK has simply lost; abandoned; surrendered; supinely given up as part of our membership of the EU.”

The opposite is the case: he rightly points out that British governments passed green energy laws that have “UK steelmakers facing energy costs as much as 80 per cent higher than the EU median”, but doesn’t see that proves Britain has kept its sovereignty. He even protests that Port Talbot suffers from his government’s “general desire to suck up to the Chinese”.

Fair enough, but the reason there are no US-style anti-dumping tariffs against the Chinese is because our government exerts its sovereignty to block the rest of the EU from excluding Chinese steel.

That’s not Brussels imposing on us, but vice-versa.

As for Boris in China, he has oozed about a “golden era” of China-UK relations, grovelling over “this avalanche, this bow-wave of Chinese investment” for his London property projects, selling off the capital.

Yet seeking weapons in the cause of Brexit, he casually trashes his relations with China. What kind of leader would he be?

This warfare has broken out among the Tories already — with three long months still to go. So fascinating is this knock-down fight to the death that there is a danger the EU debate will be conducted entirely within Tory ranks.

Blue-on-blue fights make better entertainment, and broadcasters seem to regard that as balanced. But it isn’t.

Boringly united Labour gets ignored in the cacophony of clashing Tories. Labour, its MPs, unions and prominent figures, have been almost solidly pro-European for 25 years — though often cowardly: Tony Blair made no pro-EU speeches except when abroad, he and Gordon Brown approaching Brussels as a foe with their “red line” demands.

This is the moment when Labour is speaking unequivocally in the national interest, as the Tory party implodes. It doesn’t matter if it helps save Cameron and Osborne’s bacon: what matters is that Tory and Ukip outers are defeated forever. Jeremy Corbyn, it’s promised, is onside, but he will make just one EU speech before the 5 May local elections — and that risks being a confused message. So far it’s billed not as a “yes but” speech but as a “yes and”, laying out the Europe of his dreams, not the one that is.

Expect an internal tussle over the final draft — but if that’s what he ends up saying, he risks irrelevance. This is a yes/no binary battle where nuance has long since fled the field.

What’s needed is a no-holds-barred belter. It would help in the May elections if Labour had already made its mark. But the official view is that it won’t turn up the referendum volume until the final six-week “short campaign” after 5 May. Labour MPs and councillors of all hues that I’ve spoken to are reluctant to mix the two campaigns, but that’s a cardinal error.

It leaves Labour sidelined and likely to do less well in May. What a mistake to hold back when Zac Goldsmith, arch anti-EU Tory, can be seen off by Labour’s Sadiq Khan on the damage Brexit would do to London.

What’s needed is a roadshow of barnstorming Labour rallies featuring the united forces of Corbyn and Hilary Benn, John McDonnell and Alan Johnson, Chuka Umunna, Yvette Cooper, Emma Reynolds, Lisa Nandy — all reaching across Labour’s own deep divide; an eye-catching show of unity in contrast to the Tory civil war. After May, that’s promised, better late than never.

But Conservative associations are ordered to stay out of this campaign. If Cameron is now in a state of high anxiety, here’s something he can do. Old voters won him the election, but in the referendum he needs the pro-Labour young, many fallen off the register due to his changes. There’s time to make it easier for the young to vote.

Millions will still be in colleges on 23 June, so let colleges register them. Above all, let people register on election day as they vote. That, says the Electoral Reform Society, can increase turnout by 6 per cent among the footloose young. The vote is perilously close. Cameron’s party is split beyond repair — and by the oddest quirk of fate, he needs every type of Labour supporter to save the day.

— Guardian News & Media Ltd

Polly Toynbee is a columnist for the Guardian. She was formerly BBC social affairs editor, columnist and associate editor of the Independent