If some Pashtun brigand could be persuaded for a fee to hand Osama Bin Laden over to US jurisdiction, a decent Washington lawyer might find narrow ground for mitigation in a resulting trial. Osama was a placid, diffident mummy's boy who, in the best tradition of mass murderers, was said as a child to have kept himself to himself.

He was neglected by his construction tycoon father, Mohamed, which is unsurprising, for at the time of Mohamed's death in a plane crash in 1967 Osama was one of 54 children. Bin Laden Sr was an energetic old goat with a glass eye that swivelled disconcertingly, but this did not prevent him collecting wives at will. Osama's mother, Alia, was 14 when she was married off to Mohamed, and he was born the following year. Shortly afterwards, Mohamed divorced her, which was his habit with his less socially distinguished brides. Osama evidently resented this shabby behaviour, and it was said he could not sleep when he sensed his mother was upset.

There is a latent class aspect to the Bin Laden story that Steve Coll, a distinguished American journalist, rather understates - a British author might have been tempted to develop this theme. The Bin Ladens were Yemeni tribesmen who migrated to Saudi Arabia to make their fortune. As oil revenues began to flow in the 1950s, Mohamed and his brother made themselves indispensable to the ruling family, building their hideous palaces and the kingdom's first significant infrastructure projects. In 1952, the royal family went on a car-buying binge, purchasing 800 vehicles as gifts for favourites. When the princes complained there was nowhere to drive, Mohamed was called in to lay asphalt around the kingdom.

The extended Bin Laden family became rich, but they were never regarded as entirely socially acceptable. Thus, though the legions of sons could indulge in the standard Arab-playboy pursuits of highperformance cars, prostitutes, private planes and so forth, they could not marry high into Saudi society, and this seems to have hurt.

Perhaps it is to his credit that Osama reacted so strongly against the vulgarity and corruption of the world into which he was born. Although in his later teens he seems to have been as highly sexed as his father (he married his 14-year-old first cousin when he was 17, mainly so that he could have regular, legitimate sex), he never cared for the baubles that obsessed his 24 half-brothers. Many of the children were educated abroad, mainly in America, and Mohamed's favourites, particularly the eldest Salem and his brother Bakr, spent much of their time in the West, moving from home to home in private jets.

Salem, who was groomed as Mohamed's business successor, spent most of his adult life circling the globe with a briefcase stuffed with cash, buying cars and light aircraft. When he underwent surgery for piles in New York, he persuaded a friend to photograph the procedure, and created a multimedia medley of pictures set to music that he showed Saudi royalty, including Crown Prince Fahd. Like his father, Salem died in a plane crash: he flew himself into power cables.

Another son, Yeslam, set himself up in Geneva as the head of an investment house, taking Swiss citizenship and then producing a line of designer goods and perfume. Like many of his brothers and half-brothers, his principal activity was shopping - in the mid-1980s, he owned 500 pairs of shoes, hundreds of suits and more than a dozen luxury cars. The wider family's enthusiasm for foreign travel is reflected in the now famous picture of the clan on holiday in Sweden in 1971, though Coll is clear that, contrary to popular belief, Osama is not in the picture. Instead, he immersed himself in religious education and became a stickler for his interpretation of Koranic teaching. His children were not allowed to drink through straws because these had not existed during the Prophet's lifetime;

he would avert his eyes from the family maid, and his wives had to be fully veiled at all times.

He was driven initially by his loathing of Saudi society and its ruling family. He hated Jews, of course, who, in the face of heroic Palestinian youths, behave like “agitated wild asses fleeing from a lion”. But his anti-Americanism came later and developed as a by-product of his violent rejection of the house of Al-Saud and all it stood for.

Coll has written a fascinating study of the Bin Laden family, a dynasty that is in many ways more interesting than Osama himself. Sometimes the layers of research, based on numerous interviews, can be heavygoing, and one yearns for a few more of Coll's occasional light touches. The small details are often the most revealing: officially, Osama took a strict Muslim line against usury. Yet he cheerfully totted up the interest accruing in the numbered Swiss bank account he kept to hold the dividends from the family business. And that business had benefited mightily from building roads and bases for the American military in Saudi Arabia and Kuwait during the first Iraq war. (The presence of infidel troops around the holy sites, of course, was one of Osama's principal justifications for jihad.)

There are occasional moments of bathetic humour in this grim family saga. “What's your brother up to these days?” Prince Charles asked Bakr Bin Laden at a reception in Whitehall in 2000 (if only we had known). Then we see Osama appearing on an Al-Qaeda video marking the sixth anniversary of 9/11. He delivers a pompous essay to camera about the state of his war of terror in which he denounces the normal suspects, before diverting to praise, magnificently, Noam Chomsky.

Coll captures well the image of the ageing terrorist leader, nattily dressed in a striking formal gold robe, yet he is baggy-eyed and his health seems to be declining as he approaches 50. Coll notes that if you look closely at the grainy video you can see that, since his last filmed propaganda performance, the man who solemnly condemns the materialistic and narcissistic West has taken the trouble to dye the grey streaks out of his beard.

The Bin Ladens: The Story of a Family and its Fortune by Steve Coll
Allen Lane £25 pp687

Like father, like son?

Osama Bin Laden is reckoned to have sired 23 children by five wives. Many are now in Saudi Arabia where they enjoy the perks of Bin Laden clan membership. Osama's eldest son, Abdullah, owns Fame Advertising, a Jeddah-based agency. Its brochures boast: ‘Fame Advertising events are novel, planned meticulously and executed with efficiency.' An echo of papa's methodology? Quite possibly, though their visions of an ‘event' differ: the Fame website features lots of bright coloured balloons and, tactfully, no fireworks.

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