John Rentoul: Ed saved Gordon to get his job

The younger Miliband could have helped unseat the former leader, but what good would that have done his own chances?

The "goose plot" on New Year's Eve seems like ancient history, although it was only 11 months ago. Yet it is all too pertinent to Labour's present problems.

The details of the plot, hatched over a roast goose dinner at the Suffolk weekend home of Harriet Harman and her husband Jack Dromey, were revealed in The Times on Friday. We already knew that Harman had told some colleagues that she would try to force Gordon Brown to resign. Geoff Hoon, one of the plotters, told Andrew Rawnsley, for the revised paperback edition of his The End of the Party: "She explicitly told me that she would tell Gordon to go. She felt it was her duty and obligation in order to save the party."

Now we know that there was an actual gathering of named people – well, Patricia Hewitt, the other public face of the plot, and "at least two other senior Labour MPs" – on a particular date. Indeed, with each successive draft of history, the Hewitt-Hoon plot, which seemed the wettest of fireworks at the time, becomes the most serious of the recurring threats to Brown's premiership. It was sprung while Brown was answering Prime Minister's Questions on 6 January this year, when Hewitt and Hoon sent a joint email to Labour MPs calling for a leadership election. They expected Harman, Jack Straw, Bob Ainsworth (the Defence Secretary) and unnamed others in the Cabinet to join them. But nothing happened.

The second volume of Chris Mullin's diaries, published in August, records a conversation he had with a Cabinet minister three weeks later, in which Mullin commented that Hoon's plot had been "a misjudgement". The Cabinet minister replied: "No. He was betrayed."

Mullin asked: "You mean he was expecting a senior member of the Cabinet to join him?"

"Yes."

"A vague assurance or a promise?"

"A promise."

"Who?"

"Ah, that will have to wait for my memoirs."

Now we can guess that this promise was made by Harman, or, less probably, Straw. Hoon also told Rawnsley: "I had it, on absolutely categorical authority, that Jack was going to do the business." In an interview yesterday, Straw denied it, saying he "had no idea" what Hoon and Hewitt were about to do. And when it came to it, the Cabinet failed to act. Hoon was on Newsnight that evening, admitting that the whole thing had been a miserable failure.

Why does this matter now? Nothing happened; Labour lost the election; the caravan moved on. But the more we know about how close the plot came to succeeding, the more we must ask about Ed Miliband's role. Miliband, we have since learnt, is ruthless in the matter of his brother. But this was a ruthlessness in pursuit of his own advancement. When he had a chance to show ruthlessness in the cause of maximising Labour's chances at the election, he suddenly discovered an excess of ruth. He could have tipped the balance of the plot, and if Labour had switched leader three or four months before the election, it could have won more seats.

But had the party changed leader, David Miliband would almost certainly have become prime minister. Home Secretary Alan Johnson, the other leading candidate, had hinted that he would defer to him. And, although Ed Miliband started his political career as Harman's researcher, she had indicated to the plotters that she favoured his brother as the best alternative to Brown – as confirmed in another book, by my good colleague Steve Richards, Whatever It Takes.

So Ed Miliband put his personal ambition first, and stood by a prime minister who was leading the party to defeat. He wasn't alone. Others made the cowardly argument that it was "too late". But it was specially convenient for him. He then seemed to continue to promote his own interests in the talks with the Liberal Democrats after the election.

David Laws, one of the Lib Dem negotiating team, says in his book, out tomorrow, that Ed Miliband became noticeably less keen on the idea of a Lib-Lab deal the moment it became clear that Gordon Brown would have to step down to make it possible. Because David Miliband would have stepped up. The prospect of a successful deal between Labour and the Lib Dems might have been remote, but it could be argued that, with brio and tempo, pre-empting David Cameron's bold offer of a full coalition, it might have stood a chance. Ed Miliband helped to kill it off.

The Lib Dems recognised that his leadership ambitions were part of the subtext of the negotiations. Laws says that, when he raised public sector pensions reform, "Miliband looked horrified". Miliband said: "Oh no. We cannot go further than our existing agreements with the unions." Danny Alexander joked: "That sounds like a line from your Labour leadership campaign!" Laws reports that "Miliband tried to look mystified".

Well, now it is Ed Miliband's turn to worry about plots. There were disloyal whispers at Westminster last week. Anonymous speculation about Brownites organising for Yvette Cooper to succeed him. Sarcasm about when he was going to start in his new job. Grumbles about his breaking his paternity leave on Friday to provide a soundbite for TV news on Lord Young's resignation – a Tory bad news story that needed no help from him – instead of to surprise us with his plans, say, to be tough on immigration. Too many Labour MPs fear that he has made a weak start and is not going to cut it.

Historically, the Labour Party has been reluctant to remove incumbent leaders. With the ambiguous exception of the most successful one, they have all resigned voluntarily. The question is whether, if Ed Miliband fails to rise to the challenge, this time the party will kick the habit.

He has to hope that Harman has not cooked his goose.

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