Keir Starmer left Downing Street with a resignation speech, but his government just dropped a multi-billion-pound landmine right in the middle of Andy Burnham’s path to power.
The ink is barely dry on the newly published Defence Investment Plan. On the surface, it looks like a grand statement of national intent. A massive £298 billion commitment over the next four years. A promise to ramp up defence spending to 2.7% of GDP by 2029, with a long-term target of 3.5% by 2035. Defence Minister Luke Pollard stood at the dispatch box to cheerhide a historic investment in military technology, autonomous drones, and naval base upgrades.
But look past the flag-waving. There is a massive catch.
This ambitious blueprint leaves a gaping fiscal hole that the next prime minister must fill. Pollard openly admitted that whoever Burnham appoints as chancellor will need to find an extra £4.7 billion to make these numbers work. It is a classic Westminster parting gift. One leadership team sets the targets, gets the positive headlines, and leaves the next team to figure out how to pay the bill.
For Burnham, who just made a dramatic return to Westminster via the Makerfield by-election, this is an immediate reality check. He is cruising toward a coronation as Labour leader and prime minister by the end of the summer. He wants to talk about devolution. He wants to talk about building a "No 10 North" in Manchester. He wants a ten-year mission to raise living standards through public control of buses, trains, and water. Instead, his first major act will involve a brutal choice between funding frontline public services or buying deep precision strike weapons.
The Billions Missing From the Headlines
The numbers in the Defence Investment Plan sound impressive because they are meant to. Spending £74 billion on the armed forces next year is a huge leap from previous years. The plan commits £26 billion to upgrade naval bases like Devonport and Faslane. It puts £8.6 billion into the Global Combat Air Programme alongside Japan and Italy. There is even £9 billion set aside to fix awful military housing.
It sounds great on paper. But the funding mechanism is dangerously vague.
The British economy is already buckling under the economic fallout of international conflicts, including the escalating situation between the US, Israel, and Iran. The state balance sheet has no spare cash. By locking in a 27% real-terms increase in defence spending compared to 2023 levels, Starmer’s outgoing team has effectively boxed Burnham into a corner.
If Burnham accepts the plan, he has to find that missing £4.7 billion. Where does it come from? He can raise taxes, which will instantly alienate voters who are already facing rising energy bills as the Ofgem price cap ticks upward. He can borrow more, which risks terrifying the international bond markets that he has spent weeks trying to soothe. Or he can cut spending in other departments, which would completely destroy his promise to rebuild Britain’s social fabric.
It is a trap. Pure and simple.
The Battle for Number 11
This funding crisis makes Burnham’s choice of chancellor the most explosive decision of his young leadership. Right now, a vicious proxy war is being fought behind the scenes between different wings of the Labour Party and the trade unions.
On one side stands Ed Miliband. He is the choice of the soft left and has the backing of Andrea Egan, the head of Unison, Britain’s largest public sector union. Miliband’s allies think he has the nerve to break traditional Treasury orthodoxy and fund radical domestic projects.
But big business and major industrial unions like GMB and Unite are terrified of Miliband. They worry his absolute focus on net-zero targets will kill off jobs in the North Sea oil and gas sectors. They think putting Miliband in the Treasury will cause the markets to panic.
On the other side is Wes Streeting. He represents the Blairite, business-friendly wing of the party. Streeting would reassure international investors and the right-wing press. He would keep a tight grip on the purse strings. But putting Streeting in No 11 means Burnham can basically kiss his radical spending plans goodbye. Streeting will not hesitate to tell Burnham that the money for nationalising utilities or boosting local welfare simply does not exist.
The defence shortfall forces this issue to a head before Burnham even takes the keys to Downing Street. A Miliband treasury might try to borrow the extra billions for the military while trying to fund social care, risking a market backlash. A Streeting treasury would likely demand deep cuts elsewhere to keep the military happy, sparking an immediate rebellion among Labour backbenchers.
Manchesterism Meets Military Reality
During his speech at the People’s History Museum in Manchester, Burnham outlined what he calls "Manchesterism." It is his personal brand of business-friendly socialism. He wants to move the centre of political gravity away from London. He talks about giving everyday people hope, ensuring they can afford a holiday or a night out.
That rhetoric is about to clash hard with global reality.
The Defence Investment Plan is not optional. The UK made a firm promise to its NATO allies to hit these targets. With a volatile geopolitical climate, backtracking on military spending would look incredibly weak on the world stage. Donald Trump has already publicly called Burnham "extremely liberal." If Burnham begins his premiership by trimming the defence budget to fund local bus routes in Greater Manchester, his international credibility will be shot before he even attends his first international summit.
So, Burnham has to play the game. He has to pretend he can afford a hybrid Royal Navy, thousands of new autonomous drone systems, and an AI defence taskforce, while simultaneously funding a National Care Service.
It is an impossible balancing act. The math simply does not work.
What Happens Next
Burnham cannot afford to drift through his first few weeks in office on a wave of good vibes and regional optimism. The honeymoon will be non-existent. The parliamentary timetable means nominations close in mid-July, and if he remains unchallenged, he will be prime minister within weeks.
He needs to take three specific actions right now to avoid getting blindsided by this fiscal mess.
First, he has to announce his chancellor immediately to end the toxic briefing wars between Miliband and Streeting’s camps. Leaving the Treasury in limbo while a £4.7 billion hole sits on the desk is total madness.
Second, he must order a rapid, independent audit of the Defence Investment Plan the moment he enters Downing Street. His team needs to figure out exactly which parts of that £298 billion package can be delayed, reshaped, or tied directly to British manufacturing jobs to stimulate domestic growth.
Finally, he needs to be honest with the public about the trade-offs. He cannot promise a total transformation of the British state while inheriting a war-footing defence budget without explaining who is going to pay for it.
The transition from regional mayor to prime minister is brutal. Burnham is about to find out that controlling the streets of Manchester is nothing compared to managing the compounding crises of a bankrupt state in a dangerous world.
