Can any new leader restore calm and order to the Tory party?

There was only one lesson to be drawn from last night's Peston show: the Conservative Party is in a right old state. On it we had four senior Tory MPs who support four different candidates to be leader: the Treasury minister Lucy Frazer who backs Rishi Sunak, the friend of Boris Johnson Jake Berry for Tom Tugenhadt, Bob Seely for Penny Mordaunt, and Steve Baker for Suella Braverman.

They tried to be measured and collegiate. But for most of the hour viewers saw blue-on-blue arguments, mostly about why their respective candidate was better than the others, who was truest to the Brexit cause and whether a true Tory would cut taxes now or only when the public finances are in better shape.

Also, to boot, they manifested shades from sadness to fury with the soon-to-depart PM, Boris Johnson.

What we have therefore is a ruling party riven by ideology, notably who's true to Brexit and can be trusted to shrink the public sector and welfare state, and by personal animosities, or who's been unforgivably treacherous to Johnson, and by naked personal ambition.

The problem, as a Tory still in the Cabinet confided to me, is that letting it all hang out in this way is desperately addictive.

What it means is that when the contest is over and the adrenaline rush subsides for MPs and ministers, they'll want another hit - and the arguments will start up all over again.

The point is that if history is any guide, the chances of peace and harmony breaking out amongst Tory MPs after the shock of brutally deposing a leader - whoever wins the contest to become their new leader and PM - are vanishingly small.

Let's take two possible scenarios.

First case: Sunak gets through the parliamentary stage of the contest and overcomes the wariness of Tory members to emerge victorious.

Is it really plausible that Johnson loyalists - like Jacob Rees-Mogg and Nadine Dorries who accuse Sunak of being "a socialist" or worse (!) - would in those circumstances become his silent lap dogs? Or would they constantly bark about how he's betraying the causes of shrinking the state and promoting liberty?

I think we know.

Or what about if the MPs end up backing Sunak by a clear majority, but then the members were to choose the runner-up - which on current projections would be Penny Mordaunt or Liz Truss.

Is it remotely plausible that Mordaunt or Truss as PM would have authority over Tory MPs if more than half of them wanted a different leader? Or would the in-coming premier be surrounded by doubters and troublemakers?

Again, I think we know.

The risk for the Tory party is that it will become hooked on civil war in the way that Labour became so addicted under Jeremy Corbyn.

The only winners from this mess are the Labour Party and other opposition parties.

It was, Tory MPs say, unsustainable for them to stick with a PM whose credibility and ability to lead had been fatally undermined by what was widely seen as his pathological dishonesty. The Tory party as Humpty Dumpty fell off the wall.

Those vying to replace Johnson will have to put Humpty back together again. And in the worst economic conditions for decades. Good luck to each and every one.

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