kai bird & martin sherwin american prometheus

'God knows I'm not the simplest person', the American physicist I.I. Rabi once observed. 'But compared to Oppenheimer I'm very, very simple.' J. Robert Oppenheimer was one of the seminal figures of 20th century America, whose very complexity summed up the political and ethical dilemmas of 20th century America. He was the 'father of the atomic bomb' whose opposition to America's nuclear policy helped trigger his spectacular downfall; one of the great theoretical physicists of the century who revelled in the mysticism of Hindu scriptures; a communist fellow traveller and unswerving American patriot; a deeply ethical figure who was nevertheless willing to betray his friends to protect himself from red-baiters; a man who calculated how best to destroy Hiroshima and Nagasaki even as he worried that he had 'blood on his hands'.

Robert Oppenheimer, the historian David Hollinger has written, 'was an expanse on which was worked out a multitude of the scientific, governmental, ideological, military and dynamics of the middle decades of the 20th century in the United States'. His centrality to the American Century has created over the years a veritable industry of Oppenheimer books. No previous biography has, however, matched the power, range and sheer lucidity that Martin Sherwin and Kai Bird bring to American Prometheus. Twenty-five years in the making, its combination of meticulous scholarship and felicitous prose grasps the drama of Oppenheimer's life in all its riveting complexity.

Oppenheimer was born in New York in 1903, into a wealthy, cultured and secular Jewish family. He was recognised as bright and sensitive. Or, as he put it, 'I was an unctuous, repulsively good little boy'. He studied science at Harvard, read Proust and Eliot, wrote poetry and painted landscapes. On a trip to Europe, Oppenheimer discovered the heady science of quantum physics, virtually unknown in 1920s America. He was entranced - theoretical, mathematical and mystical, the new physics seemed designed for Oppenheimer's mercurial mind. He built a reputation as America's most brilliant young physicist, predicting the existence of both anti-matter and black holes well before either was discovered experimentally. Yet he always fell short of true achievement. Oppenheimer's imagination was boundless, but he lacked the application necessary to transform fleeting insights into real scientific breakthroughs.

Towards the end of the 1930s Oppenheimer stumbled into politics. The question that was to haunt his later life was whether he had ever been a member of the Communist Party. Oppenheimer always denied membership, and decades of often illegal and unethical FBI investigation produced no evidence to the contrary. Nor does Sherwin and Bird's careful sifting of the evidence.

Oppenheimer was in fact a liberal who supported causes that today would seem uncontroversial even to most conservatives: opposition to segregation, support for decent working conditions, the defence of democracy in Spain. In the 1930s, though, the FBI viewed such causes as the mark of a dangerous revolutionary. That said less about Oppenheimer's politics than about the illiberalism of pre-war America.

By 1939 Oppenheimer had discovered a new cause: how to prevent the Nazis from winning the race to build an atomic bomb. When the Americans set up the Manhattan Project to produce their own Bomb, Oppenheimer was chosen to lead it. Even his friends were shocked that so unworldly figure should be appointed to such a crucial and sensitive post, yet he proved an inspired choice. The Manhattan Project transformed him from a scientific dilettante to a brilliant and creative leader.

In the end the Bomb was used not against the Nazis but on Japan. The obliteration of Hiroshima and Nagasaki shocked many of the scientists - especially as Japan had, to all intents and purposes, already been defeated. Typically, Oppenheimer discovered enough ethical wriggle room both to worry about the use of the Bomb on civilians and to suggest that he never regretted his role in making the bombings possible.

The success of the Manhattan Project turned Oppenheimer into both a scientific celebrity and a Washington operator. He became central to debates, inside and outside government, about American nuclear policy. He clearly loved being a Washington insider and censored his political activities to fit in. Yet his opposition to the main thrust of US policy made him powerful enemies. He demanded openness about America's nuclear programme, and opposed the building of the more powerful H-bomb, at a time when the burgeoning Cold War was pushing American policy makers in the opposite direction.

Oppenheimer's enemies launched a campaign to bring him down, which culminated in 1954 in a month-long review of Oppenheimer's security clearance conducted by the Atomic Energy Commission. It was less a review than a show trial, orchestrated by his nemesis Lewis Strauss, aide to President Truman and chairman of the AEC, with considerable help from J Edgar Hoover. Albert Einstein, Oppenheimer's colleague at Princeton, advised him not to cooperate with what was clearly a kangaroo court. But Oppenheimer was too wedded to being an insider simply to walk away. 'The trouble with Oppenheimer', Einstein wryly observed, 'is that he loves a woman who does not love him: the US government'.

The result was public humiliation. Oppenheimer was found guilty of 'substantial defects of character', lost his security clearance and never worked for the government again.

The vicissitudes of Oppenheimer's life reflected the contradictions and dilemmas of twentieth century America. America allowed Oppenheimer's extraordinary talent to flourish as perhaps no other nation would have. It also ultimately betrayed him. The story of 'The triumph and tragedy of J. Robert Oppenheimer', as Bird and Sherwin show, is also the story of the triumph and tragedy of the American Century.