We have been here before. I blogged unkind things about David Miliband when he was being log-rolled by the Blairite machine, as bathed in the blood of Tony, so brilliant, so cool, so je ne sais quoi as to be very nigh compulsory.

The reality, when he didn't get the assured leadership, has been a sulking minimalist in the Commons, above all that low, grinding trouble.

Compare Margaret Beckett, his predecessor at the Foreign Office, chasing the palm, but enjoying the dust. She was avid, slippery, ultra-left in the 1960s, many-sided, hard-working, a useful pragmatist when demanding jobs came in sight – a proper politician.

Yesterday's flight to New York is Miliband's self-pity gone public. 'You'll be sorry when I'm dead.'

Anyway what are we supposed to be losing? He is spa water gone luke-warm, ex-sparkling, feeble by pre-emption. His career took off courtesy of Gordon Brown demonstrating outreach to prime Blair material. Miliband was able to run as precisely that in the leadership election.

Today, with the door open to major front bench responsibility, he is unwilling to serve the party that didn't crown him. The sulking minimalist in the Commons disdains the Cabinet. In truth David Miliband is too small for serious politics.