“In No 10, there’s nothing there: there’s nothing behind the door.” Stewart Wood, who advised Gordon Brown during his premiership, says he can understand Dominic Cummings’ desire to gather more of the levers of power into the prime minister’s hands.

“There’s a secretariat; a few clever officials are on loan; and the advisers. And that’s it,” Lord Wood says. “And the job of the adviser at No 10 is to make something happen. You’ve got to be strategic, you’ve got to bully departments, you’ve got to work with departments. The only levers you’ve got are the ministers, the special advisers.”

Many prime ministers have grappled with the challenge of how to make their manifesto promises a reality – Tony Blair sent senior advisers, Andrew Adonis for education, for example, fanning out across government to bang ministerial heads together.

Rishi Sunak could be more relaxed on public spending, hints No 10 Read more

And Theresa May’s “terrible twins”, Nick Timothy and Fiona Hill, acted as gatekeepers and enforcers, insisting they should see official papers before their boss, and delivering orders to senior figures, including ministers.

But this is a government in a particular hurry, because of the nature of its election victory. As one ally puts it, “the votes they have in their hands are not from loyalist Conservatives who like the idea that Conservatives are in the top job. They’re votes that are lent, and every day are measured against delivery. So that’s why they’re freaking out about delivery.”

The relationship with the Treasury – traditionally the bulwark against spendthrift prime ministers with crackpot plans – is critical for every government. Tensions between Gordon Brown and Tony Blair became legendary; and the final two years of May’s administration were marred by running battles with Philip Hammond over spending. David Cameron and George Osborne rarely disagreed – though Osborne has pointed out he advised his old friend and colleague against backing a referendum on EU membership.

Thursday’s showdown with Sajid Javid, culminating in the chancellor walking out, underlined the fact that Boris Johnson intends to learn the lessons from May’s administration and others that went before.

“The one thing about this No 10 team is, they’re like a really good algorithm: they actually learn from mistakes,” said one former Tory adviser. “They approach a move; they see it’s going to be blocked; and they learn from it, and go around.”

Johnson and Cummings have decided they need to build up the centre of government, boosting the firepower of No 10 in the age-old tussle with the Treasury that tends to set the direction of every government. But as well as tuning up the government machine, veteran onlookers in Westminster read another motive into Thursday’s events, too: stamping out dissent.

“They’re like, ‘the days of the wild west are over and we need to have absolute unity’,” said one senior Conservative who knows Johnson’s team well. “And that’s important, because they’re riding high at the moment – but Keir Starmer is not Jeremy Corbyn. The polls are going to narrow, Labour will probably win some seats at the council elections, and things will look very different.”

He added: “There’s no doubt what they’re demonstrating here is the necessity of loyalty to the boss. I think we have seen in both reshuffles the ruthlessness of Boris.” The same is true of special advisers – with any suspected of leaking to journalists moved.

Thursday’s moves dramatically increased the political stakes for Johnson and his team. “Cummings clearly thinks all roads lead to No 10, and No 10 makes all the decisions,” says Wood. The problem that Cummings has made for himself now is that they’ve brought everything to their door. When the mistakes come, the blame will come thick and fast to the door of No 10.”

And he has made himself a public figure. Friends say he relishes baffling journalists with his gnomic utterances – such as Tuesday’s gem about the kids’ cartoon PJ Masks – believing he can act as a lightning rod. But from Alastair Campbell, waging war on the BBC over Iraq, through Damian McBride, defenestrated for an alleged smear plot, to Timothy and Hill, sacked by May at the behest of her cabinet, once advisers become well known, it tends to be the beginning of the end.

One former government insider suggested Johnson was “wringing every drop of use” out of Cummings, in the full knowledge that he would last “from a week to a year” – and indeed Cummings suggested in the run-up to last year’s general election that he wasn’t in it for the long term.

He has also made himself the story, and as one former Tory adviser puts it: “We all know how that story ends.”