Ed: The Milibands and the Making of a Labour Leader, by Mehdi Hasan and James Macintyre, Biteback, RRP£17.99, 240 pages

Ed Miliband will never have to prove that he is ruthless: he beat his elder brother David, an admired foreign secretary, in the Labour leadership contest. He does, however, have to prove his fitness to become Britain’s prime minister.

The brothers were born within four years of each other to Ralph Miliband and his wife Marion, Jewish refugees who fled the Nazis. Ralph became a famed Marxist political scientist, deeply scornful of the Labour party and of British representative democracy; his most famous book, Parliamentary Socialism (1961) excoriates a “sick” party for its “dogmatic” adherence to the parliament in which his sons would go on to sit.

Although Ed is a careful, fluent and unhistrionic account of Miliband’s rise by present and former New Statesman political journalists Mehdi Hasan and James Macintyre, it offers too little illumination of how he and his brother came to reject their father’s politics and formed their own social democratic ideals. It also offers too few details about their beliefs.

The Milibands were raised in intellectual privilege. Ralph’s rapid rise to prominence brought luminaries such as Tony Benn to a hospitable dinner table where politics, policy and the imperatives of social change were the conversational currency, and secured an Anglo-American support network of radicals, media tyros and scholars.

Ed’s education in economics was pursued at Oxford, the London School of Economics and Harvard – and in the private cabinet of Gordon Brown, when Brown was shadow chancellor. David, meanwhile, was a senior aide to Tony Blair. They were thus on opposing sides of the Brown-Blair wars, which were fuelled by Brown’s rage, contempt and disloyalty towards his prime minister. “Little” Ed, unlike “Big” Ed (Balls, Brown’s closest adviser), stayed out of these often bloody power struggles.

When Brown lost the 2010 election, Ed had already largely decided to run for the Labour leadership, which meant taking on front-runner David. He won, write Hasan and Macintyre, essentially because he was charming and David abrupt; had the elder Miliband been nicer to only half a dozen Labour MPs, he would have won. It’s a telling and possibly accurate assessment.

Now Labour leader, Ed has his charm, intelligence, nerve and ambition going for him. Against him is his attachment to an apparently shallow dismissal of New Labour in favour of “values”, as slippery a concept as any. His view of Iraq – Ed convincingly shows he was always against the invasion – is the bellwether. In his leadership acceptance speech, he said “we were wrong to take Britain to war”. In a few phrases, he aligned himself to the view that Saddam’s threat to the region, his monstrous invasions, genocidal massacres and clear intention to acquire weapons of mass destruction matter less than Blair’s “lies” (actually, mistakes based on too-thin intelligence) about WMD.

If New Labour must be junked, “Blue Labour” – inspired by scholar Lord Maurice Glasman, a speechwriter for Ed – provides some filling for the resulting hole. Blue Labour stresses a concentration on improving the lives of the working class. It is a powerful antidote to New Labour’s radical chic tendencies. Yet Glasman’s version entails questioning the party’s commitment to the European Union, multiculturalism and free market-led growth – and its appeal to the politically centrist middle class.

Ed is an efficient portrait of one who has spent a life immersed in political discussion, study and inner-party manoeuvring. That is no disqualification: modern politicians need to be professionals. But in a world in which image is much of the story, Miliband has not yet acquired the demeanour of a future prime minister; and in a world in which substance still matters, he has yet to show what distinct politics he offers.

John Lloyd is an FT columnist

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