Little, Brown £20 pp349

We have had to readjust our view of the world several times since the destruction of the World Trade Center, as what at first appeared to be the work of Arab lunatics quickly turned into a war on terror and then a clash of civilisations. In recent months, President Bush has refined the parameters still further, and now talks not of bringing democracy to the Middle East but of defeating radical Islam.

What happens next is anyone’s guess. But while we wait for a pullout from Iraq, perhaps, or a workable status quo in Afghanistan, it is worth pausing to look back at how this started. Charles Allen’s latest book is the perfect aid, because, if his thesis is to be believed, the current conflict has its roots not in 2001 Manhattan or 1948 Israel, but with the emergence of the Wahhabi cult in 18th-century Arabia.

Wahhabism started much like any other reforming religious movement, with a call to purity, a restoration of Islamic first principles. But in the 1740s, Muhammad ibn Abd al-Wahhab went further. In The Book of Unity, he claimed that the path to salvation could be achieved only by a literalist, uncompromising devotion to Islam “as well as by hate and hostility to infidels and polytheists”. This aggressive stance ran contrary to Islamic attitudes and even al-Wahhab’s family objected. Inevitably, it brought him into conflict with secular power and we would be unlikely to have heard of al-Wahhab’s name had he not found a powerful new convert, a tribal leader called Muhammad ibn Saud. Al-Wahhab and Ibn Saud swore an oath of allegiance after which the prince was known as the Emir or leader and the cleric was titled Sheikh ul-Islam.

But this is not just a history of the progress of Wahhab’s cult, for Allen has a larger, more politically relevant project, to draw a line from the rise of al-Wahhab to the emergence of Osama Bin Laden and his Wahhabi-inspired killers. Allen tells this complex story with concision, insight and wide-ranging vision, beginning with the birth of the cult and then charting its advance from al-Wahhab’s introduction of firearms to warriors who had only ever used sword and spear, to the inevitable outcome at the start of the 19th century, when the Wahhabis left a trail of destruction across the Muslim holy places, from Kerbala to Mecca and Medina, and defeated a sizeable Egyptian army in 1811, only to be decimated by the returning Egyptians in 1818.

The destruction of the Wahhabi army did not bring the cult to an end, but led to a Wahhabi migration to what is now Pakistan, north into Afghanistan and south into India. It is this India connection that might raise eyebrows, for here Allen suggests that the Wahhabis were to a large extent responsible for the outbreak of the uprising against British rule in 1857. The evidence is compelling, if not conclusive, and includes the appearance of the Wahhabi war song, the Risala Jihad (Army of Holy War), in Delhi two years before the violence erupted. What isn’t to be disputed is that Wahhabism flourished in the religious school established in Deoband, northern India, in 1866.

From India, Allen returns to Arabia, tracing the rise of the house of Saud and with it of modern Wahhabism. Here, too, he will ruffle feathers with his suggestion “that [TE] Lawrence got it wrong”, that the man of interest was not Lawrence’s hero Prince Faisal but the founder of Saudi Arabia, Ibn Saud. He has a point, for it was Ibn Saud who had a Wahhabi history and key texts printed in Bombay, and Ibn Saud who managed to unite the Arabian tribes and please the Wahhabis while embracing cars, telephones and many other things not mentioned in the Koran. From Ibn Saud it is but a short jump, via petrodollars, global politics and Russian involvement in Afghanistan, to Osama Bin Laden.

Allen makes no attempt to hide his aversion to Wahhabism, which he calls “holier-than-thou, confrontational and heartless”. The book might have been even better had he kept such sentiments off the page. Nevertheless, this long, bloody and commandingly told story does what we long for history to do: tells a tale of long ago that throws new if uncomfortable light on our world.

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