Why did Starmer cut the winter fuel allowance? It’s called Treasury brain – and that spells trouble

‘Power gravitates to the Treasury’: chancellor of the exchequer Rachel Reeves on 5 July, the day after the general election. Photograph: Toby Melville/Reuters

An unwritten law of Westminster mechanics states that power, in the absence of a countervailing force, gravitates to the Treasury.

The governing agenda can be set in No 10, but a prime minister has few instruments of control as immediate and far-reaching as the purse strings in a chancellor’s hand.