Perhaps this time it really is all over for Boris Johnson. Downing Street clearly overestimated Tory support for the Prime Minister this week. The Government’s last-minute U-turn over an amendment to delay a parliamentary partygate investigation highlights the fact that many Conservatives are no longer willing to throw “Big Dog” a bone.

As Sir Geoffrey Clifton-Brown, Treasurer of the 1922 Committee of Tory MPs, put it: “The dial has shifted today, partly as a result of the way this whole matter has been handled and also partly I think that more colleagues have been able to get back to their constituencies and hear what people are saying on the doorsteps.”

So, bar a clique of cheerleaders, Mr Johnson is being held in place for now by a lack of any realistic alternative. That’s hardly a strong case for his premiership. It is in nobody’s interests for the Prime Minister to cling to his job, constantly looking over his shoulder, and able to achieve nothing for the country.

No, if the Prime Minister is serious about both staying in power and winning the next election, No 10 needs to show the positive case for his rule and “build back Boris”.

The Prime Minister’s key selling point has always been that he could spread optimism, but that has disappeared amid Covid, the cost-of-living crisis, and now partygate.

But that is what he needs to get back, if he is to have any chance of survival.

Like the girl with the curl in the middle of her forehead, when he’s good, the Prime Minister is very, very good. Even Emily Thornberry, the shadow attorney general, was forced to admit this week that he had performed “very well” on Ukraine and was “brave” to visit President Zelensky in war-torn Kyiv.

There is also no doubt that he has got the big calls right on vaccines and, eventually, lockdown.

There was a great deal more opposition from figures such as Professor Chris Whitty and other scientists to his decision to end all the pandemic restrictions on February 24 than perhaps is widely appreciated.

The chief medical officer strongly cautioned against it, but Mr Johnson finally showed some cojones and we are now back to something resembling mask-less normality – and all without collapsing the NHS.

The recently announced policy to process illegal immigrants trying to reach Britain by boat in Rwanda also showed courage, thanks largely to the fact Priti Patel is better equipped in that department than most of her male colleagues. But it was with good reason that the Prime Minister announced it. He knew that, beyond the bleating of the Left (and the clergy), the silent majority were pleased that at last something was being done to tackle the scourge of people-traffickers profiting from illegal immigration via rubber dinghies.

This could apply to any leader, but it especially applies to Mr Johnson: he is at his best when he is at his boldest. He only really does well when he shows courage and drive.

Every day now needs to be Boris on the streets of Kyiv, in metaphorical terms at least. Anything less is not just going to be bad for the Prime Minister; to go back to the nursery rhyme with the similarly hirsute protagonist, it is going to be horrid.

Johnson also reigns supreme when he sticks to Tory principles.

At City Hall, the whole mantra when he was London mayor was about being tough on crime, running a tight ship and throwing money at the projects that really mattered to the public. Voters in the normally Left-leaning capital were so clear about what he stood for that they elected him twice.

Compare that to now and Conservative voters are, at best, confused. Despite the billions ministers continue to throw around with abandon, a YouGov poll this week found that two thirds of Britons think the Government is currently handling the economy poorly.

According to the pollster, there is a “holy trinity” of targets that Labour must meet in order to win the next election: being ahead in voting intention, being seen to have the best candidate for prime minister, and superior economic management. Although they are only six points ahead in the voting intention stakes, the Labour Party, which has a tendency to splash more cash than Sir Elton John at Interflora, is now viewed by the public as almost budgetarily sound.

Of the seven economic trackers put to those surveyed, the only one in which the Conservatives were ahead was: “Which party would be better to tackle the government deficit?” They only came out narrowly ahead by 28 per cent to Labour’s 20 per cent.

Even more worryingly for the Tories, when asked who was best at keeping prices down, 28 per cent said Labour and just 15 per cent said the supposedly fiscally disciplined Conservatives. It is frankly astonishing that an administration once so hooked on focus groups still cannot see the folly in the Health and Social Care Levy, which is actively making its core electorate poorer. (And let’s not even get started on the frankly idiotic tax on aspirational graduates, who are the only 18 to 24-year-olds ever likely to vote for the Tories).

“Streets of Kyiv Boris” would scrap the levy now, and slash the ludicrous corporation tax rise while he’s at it. How on earth can we make the most of Brexit if we are going to be less competitive in these terms than France come 2023?

Asked to rate the Government on how it was handling all the issues that matter to them – from inflation to immigration – the Tories only came out on top on defence and terrorism.

Last month, the jobless rate fell more than expected to 3.9 per cent, despite the Omicron wave, according to the Office for National Statistics. Yet still 47 per cent of those polled said that the Government was handling unemployment “badly” compared to 34 per cent who thought they were doing a good job.

What these figures show is that the public is unclear about what exactly the Government stands for.

So if Mr Johnson is going to achieve some sort of Churchillian reboot, he is going to have to show the courage to back the things that voters want him to back. And fast.

Apparently, Mr Johnson has been bounding around Downing Street calling for “a new Kate Bingham” to run the Government’s energy strategy (an idea, incidentally, that appears to have been borrowed from a Telegraph column. As George Tregarne wrote in this newspaper last month: “One option would be to appoint a Dame Kate Bingham of energy, in the mode of the wonderful woman who led the vaccine task force.”)

The Prime Minister, who has always been good on ideas (even if they have been borrowed from other people), reportedly wants seven nuclear reactors to be built “at warp speed”, as well as developing offshore wind to make us energy self-sufficient as soon as possible.

So the ambition is clearly there – now it all comes down to the execution. The whole reason Dame Kate’s vaccine task force worked is because she was bold and she was brave to bank on the various jabs she had invested in coming off. She took a gamble.

Mr Johnson has got to replace reckless policy-making with calculated risk-taking. He’s got to channel his inner journalist now, do his research on what really matters for Britain – and deliver on deadline. He got Brexit done but still needs to sort out the Northern Ireland Protocol. He needs to make good on his promises. He still has time to rescue this situation but it is not just going to require “buggering on”. It’s going to need Dunkirk levels of spirit.

He spent the first two years of his administration following the science. He must spend the next two following his instincts.