No more Mr Nice Guy? “I’m not putting up with this anymore” may as well have been the message of Sir Keir Starmer’s big speech this week, according to one senior source. Sir Keir wasn’t just listing his political priorities, he was showing what has been no secret in Westminster for a few weeks, that he has a “frustration, a genuine annoyance” according to another source, about how hard it seems to be to get things done.

The prime minister was not just sounding off at civil servants insiders claim, but trying to confront gloomy public perceptions that governments can’t really make much difference to our lives. Sir Keir is not someone who likes being told that something can’t be done.

His speech, which No 10 had been contemplating since before the Budget at the end of October, does give you and me a card with which to mark the government’s progress. It shows what the prime minister’s team has concluded is most important to the public and therefore the country’s most urgent problems to fix.

Allies of the prime minister dismiss suggestions it was yet another campaign event – after all to govern is to choose, as the saying goes – and they’ve made big decisions about what to pursue, and what, by implication, has fallen down the list.

But away from the policies, this week’s moment was Sir Keir and No 10 “stamping authority on things”, says an insider – not just in a broad political sense but also in one very specific way. Whitehall is increasingly consumed with the upcoming spending review, the moment when the Treasury spells out how much cash each department is going to get in the years to come, likely now after Easter, in May or early June. But the prime minister has very publicly set the priorities now so no one can “wriggle away from the fact No 10 will be in charge”, says the insider.

Isn’t No 10 always in charge? Well the Spending Review process was invented by then Chancellor Gordon Brown, one source recalls, to make sure that “he could control the big decisions, not Tony [Blair]”.

The pattern for years has been haggling between the chancellor at No 11 and other government departments over the sums. According to one Sir Keir ally: “The Treasury has had the pen and the meetings and the numbers, then No 10 gets involved for the political risk at the end.”

Not this time. Now the “political strategy comes first” with Sir Keir’s announcements this week, “then the pounds and pence” I’m told, with the agreement of Rachel Reeves.

There is also a hope that such a public setting of priorities (these are the prime minister’s own words) might avoid noises off in the run up to that vital review. Sir Keir has made plain what is important to him. If a minister isn’t lucky enough to have their agenda on his shopping list of priorities, the idea is that arguing privately or publicly through allies or journalists with willing pens and microphones isn’t going to make the running – “the political choices have been made”, a source says.

But guess what? It might not be quite so straightforward for the not so new PM to bare his teeth, show his frustration and then find he’s suddenly fully in control. New targets set by a new, visibly frustrated prime minister, are unlikely suddenly to persuade you all.

Another Whitehall insider told me – “I thought he managed to cosplay both Rishi and Boris in one go yesterday with six targets and the CS [civil service] stuff” – teasing him for metaphorically dressing up as not just one, but two of his predecessors. Ouch! Whereas Sir Keir has six targets, Rishi Sunak had five pledges that drove his unsuccessful time in government. And just as Sir Keir spoke of “naysayers” in his speech, Boris Johnson was fond of taking on what he described as the “doomsters” and “gloomsters”.

Sir Keir wouldn’t like the comparisons to Johnson or Sunak who he lambasted in office. He certainly wouldn’t want to give the impression he’s aping their style or strategy. But he is often accused of chopping and changing his own.

Sir Keir’s joke about being the next James Bond was just that, a joke. It’s unclear if he has ever indulged in fancy dress, certainly as an adult. But it is the case we’ve seen different versions of Sir Keir, accompanied by seeming contradictions.

There was the tough sheriff during the summer riots intent on rapidly locking up offenders, who is now exploring shorter prison sentences for some wrongdoers. He was the City schmoozer when trying to woo business to Labour’s cause, who has then slapped billions of tax on firms. There has been the prime minister who wants a radical rewiring of the state, who then appointed a classic Whitehall insider as the head of the civil service this week. And he was, of course, the aspirant party leader from Labour’s soft squidgy left that had stood alongside Jeremy Corbyn, who then disavowed him and his policies.

A senior official warns “it looks like cakeism” – the prime minister wants to have it all ways, and doesn’t want to be defined, or choose what he is really about, or maybe, the official warns, he doesn’t really know?

The long running criticism of Sir Keir is that he doesn’t have his own ideology, isn’t part of any particular political tribe and so it can be hard to work out what he is really for. A former senior official describes him as a “sole trader” in politics who will do what is required in a particular moment but doesn’t understand empathy or persuasion, telling me, “he doesn’t persuade or influence – he wants the country to eat our all bran, but he also thinks it’s beneath people to be motivated by human connection or emotion”. Another insider remarks, “his shtick is what works, so there is no ‘Starmerism’ – that means it’s difficult for the civil service to know what he stands for, or what he might instinctively want to do about most issues”.

But the prime minister’s obvious irritation act has caused genuine upset in Whitehall.

Without doubt some officials perceive his comments this week as an attack on them. They’ve come as a shock, “weird” is how one describes it and says it’s come out of nowhere. The suggestion that the civil service is happy to preside over mediocrity has genuinely surprised and caused distress among officials who feel they have been busting a gut to get to know their ministers and understand what the new government is about, and to help them achieve their goals. “The anger is real”, a senior official told me and “suggests a disconnect” between No 10 and departments where civil servants have been “working like dogs” to try to make sense of their new master’s plans.

His allies don’t, and never have pretended that Sir Keir is someone in politics to make friends. He himself freely admits he’ll have to be unpopular to get things done. They say he’s aligned with the public, he cares about what will get results, not what Westminster is preoccupied with. But that has perhaps meant that over time he’s been willing to take on different political personas, to play different parts depending on what suits him at that moment.

His shifts in position, one ally admits, mean that for “people looking to be critical of him, the Left or the Tories, that can mean he looks inconsistent”. But they say “a more fair and honest appraisal of him is that he is just focused on what works”. The word used again and again about his political character by sources close to him is “pragmatist”. The public isn’t exactly delighted with the results of politicians who have pursued ideology after all.

Politics is rarely pure, no successful leader has ever slavishly followed a predetermined path. Yet a union leader worries, “in government it’s the substance and judgement that counts. You need something to fall back on, your guiding principles that help you make those judgements”.

Consistency matters too. Sir Keir’s allies say he is much happier being the prime minister than he ever was being leader of the opposition because he can act, not just say. Yet one of the insiders I’ve talked to cautions the prime minister’s frustrations stem not from the lack of desire to make things happen in Whitehall, but a lack of clarity in his instructions to the government. “Maybe he knows how to “be” PM but not how to “do” it. They don’t actually know what they want to do beyond the level of vague generalities,” the insider argues.

But after five months in government we are seeing the prime minister trying out a new part – the frustrated boss. Pointing the finger at “naysayers”, and “blockers” whoever the people are who are wallowing in the tepid bath he described is a deliberate decision.

As Sir Keir is trying to tighten his grip on the government machine it’s the persona he is portraying in this moment.

“He’s more determined to win than people think” says a source who’s worked with the PM up close. Perhaps the only persona he truly wants to avoid is playing the losing part.

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