John Healey was a loyal Starmerite. His departure leaves the PM lonelier than ever

The story being told about Britain’s politics has begun to resemble that of the Vietnam war epic Apocalypse Now: we journey up river, along the banks of the Thames through mind-numbing atrocities to find a once-respected leader – Colonel Keir – who has cut himself off from the world and is surrounded by dismembered corpses.

For a while the Labour party imagined itself in a happier place – let’s call it Makerfield – where people could “Vote Andy” for hope and change as if the past two years never happened. But now it is being dragged back into the “heart of darkness” in Westminster with another resignation of another cabinet minister.

Though the fictional horror depicted by Francis Ford Coppola bears no resemblance to the actual government – whether you think it is living or dead – it is nonetheless a grim environment to all those who came into politics to do some good.

Keir Starmer summed it up well in a recent Substack article when he responded to Tony Blair’s own lengthy essay demanding a big-picture vision for the future. Faced with fragile public finances, struggling public services and failing public trust, the prime minister described how “government is about acting on every major problem simultaneously, balancing them against each other, and trying to get to the best situation for Britain overall”.

This is the backdrop to John Healey’s resignation as defence secretary after reportedly being told only £13.5bn – or £10bn if you discount what some have called “Treasury trickery” – had been squeezed out of other priority capital budgets for a much-needed and long-delayed plan to invest in Britain’s military.

Until Healey’s resignation letter dropped, the defence investment plan had been lazily described as merely one part of a “bucket list” of policies that Starmer was fiddling around with in the hope it would belatedly put a bit of shine on his legacy.

The reality, however, is that this was always going to be a grindingly difficult task and, whatever criticisms people might make of him, Starmer did not leave this thorniest of problems to a successor. Nor did he try to defer it with the kind of massive but unfunded spending commitments made by some of his Tory predecessors when they realised their time was up. One admiring aide describes arriving in a deserted No 10 on a weekend to find “the PM hunched over the spreadsheets, going through it line by line, over and over again”.

In the end, he did not find an answer that would satisfy his former defence secretary and all the rest who fear military underfunding has left Britain’s security in peril. Journalists who visited Makerfield took turns to predict that voters are about to deliver a byelection victory for Andy Burnham next Thursday that will propel him into Downing Street within a few weeks. Now they gasp over the latest drama from the once-loyal Healey and ask if Starmer can make it through the next few days.

That will undoubtedly drown out what Starmer wanted to say about how his carefully cultivated relationships with other leaders – in Europe and beyond – made him better placed than anyone else to meet the shortfall by building new military alliances over the next year. Yet this latest episode in a rolling crisis also, perhaps counterintuitively, makes a case for him to stay on as prime minister if only for a little longer.

Indeed, before the latest crisis, all the focus on military plans appears to have triggered some muscle memory in Starmer of the successful campaigns he fought for the Labour leadership and the general election, both of which were characterised more by discipline and organisation than inspiration.

Over the past few days he had been making a concerted effort to establish some credibility for his expressed determination to fight on. Although the prime minister had been insisting to anyone who would listen over the past month that he “will not walk away”, the assumption was that this was merely the sort of thing he would say before eventually bending his knee at Burnham’s coronation later this summer. “Journalists don’t believe him because they’re imprinting their own cynicism on him,” complained one of Starmer’s advisers.

But last weekend he sent out scores of text messages to friends and allies saying that he had decided to “fight & win” any leadership election. This was followed by phone calls to key figures across the Labour movement asking directly for their support. On Monday he assembled groups of junior ministers, all of whom had been given their first posts in government by him, around the cabinet table. Starmer sought to convince them of his determination to carry on, the danger of Labour turning back inwards when public disenchantment with politics is already so rife, and the risk of handing over Downing Street to someone he thinks is so unprepared for the job.

There was a certain awkwardness in some of these meetings because the prime minister has not always been so interested in the lower ranks of his own government. At one stage, sidelong glances were exchanged when he began extolling the virtues of a policy to the minister responsible for implementing it. Nonetheless he probably did enough to leave them with the impression that it will not be as easy as some think to prise him out.

By promising to resist any challenge, however, Starmer was not entering – let alone starting – a leadership contest so much as seeking to deter and delay it. His argument is that the fragile state of the economy and market confidence, together with global insecurity and recent outbreaks of public disorder, make this a terrible time to inflict more political chaos on the country.

He no longer repeats his much-ridiculed desire to serve a full 10 years and those around him acknowledge that the question of who is prime minister at the next election will have to be settled “at some point… just not now”. Allies are making much of a Burnham interview last week, in which he appeared to struggle with questions about fiscal rules, to emphasise his unreadiness to take over. If you want more money for defence, they say, then watch the mayor of Greater Manchester explain where he will find it. Would he cut welfare budgets when his supporters led the revolt against the government’s last effort do so? How about taking more money from the net zero agenda of his closest ally, Ed Miliband? They ask why anyone would want to start again “at the bottom of the steep learning curve we’ve been on for the past two years” with a novice prime minister who has not even been an MP for the past nine years.

One idea being discussed in Downing Street is for Starmer to respond to a Burnham byelection victory by welcoming him back, asking him to focus first on another byelection for the Manchester mayoralty he will be vacating, then offering him a cabinet job. Although they recognise Burnham would almost certainly refuse and be reluctant to delay a leadership bid when he has momentum, they still detect some hesitation in him over making the first move. For instance, even when apparently confirming he would enter a leadership race last week, he tried to claim that one had already been started by Wes Streeting, despite the former health secretary’s failure to produce the nominations from MPs needed to trigger it.

Starmer’s team think that polls showing he trails Burnham by a wide margin among the Labour members who would decide the outcome of any contest could close rapidly if the latter was seen as over-eager to get through the Downing Street door. “No one should forget that our party is always a lot more loyal to its leaders than the Tories are,” a senior adviser says.

But the prime minister has been operating for several months with key posts left vacant and often demoralised staff. One says, with dark humour: “I’m not in the room where it all happens, but I’m not even sure there is a room.” Starmer must also guard against the aggressive briefing that this week suggested he would tell any minister who supports Burnham to quit, or the relish some of his supporters are expressing over the prospect of removing Miliband – or forcing his resignation – as energy secretary, in return for the support in a leadership contest of the GMB union, which wants more drilling for fossil fuels in the North Sea.

Although there is already far too much of this kind of factional and vengeful politics characterised by violent metaphors about “civil war”, “bloodbaths” and “sieges”, the most famous quote from the crazed Colonel Kurtz in Apocalypse Now somehow seems appropriate for Starmer’s position.

I watched a snail crawl along the edge of a straight razor. That’s my dream. It’s my nightmare. Crawling, slithering, along the edge of a straight razor… and surviving.

It is doubtful that the prime minister will appreciate the comparison now, not least because Kurtz is brutally killed at the end of the film. But as he tries to traverse his dangerous path over the next few months, he may yet prove to have adapted better to such danger than his detractors think.

Tom Baldwin is the author of Keir Starmer: The Biography

Photograph by Wiktor Szymanowicz/Future Publishing via Getty Images, Pictorial Press Ltd / Alamy