Soft left senses chance to push Starmer into progressive pivot, but leftward turn would be fiercely resisted by some

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As the prime minister fought for his political life before Labour MPs at their Monday evening meeting, even hardened sceptics saw a flash of something different in Keir Starmer.

Ed Miliband, the energy secretary, said Starmer had been “liberated”. He did not have to spell out who from. His comments came 24 hours after the departure of Starmer’s chief of staff, Morgan McSweeney, a man who has shaped Labour’s modern incarnation.

It is not just this doomed government but the Labour party itself that is disappearing before our very eyes

When he does go, what will the political death certificate give as the true cause of Keir Starmer’s demise? It won’t be the Peter Mandelson scandal, the policy U-turns or the bleak nights at provincial counting centres. All these are symptoms, not the disease. No, what is turning the guy elected just 19 months ago into an ex-prime minister is the slow realisation among ministers, colleagues and voters of one essential truth about the man: there is less to him than meets the eye.

His promises get shrunk in the wash. A green new deal is jettisoned, an Employment Rights Act has a large watering can poured over it, a bold manifesto pledge to end Britain’s feudal leasehold laws suddenly grows caveats.

Aditya Chakrabortty is a Guardian columnist