We are in the midst of a “cosmic war”, a religious war quite unlike holy wars of the past. It is a conflict, the Iranian-American writer Reza Aslan tells us, in which God is believed to be directly engaged and actively supporting one side over the other. It is like a ritual drama acted out on the Earth according to a script written by God.

The chief perpetuators of cosmic war today are jihadists, radical Muslims devoted to the sole goal of fighting unbelievers. These are “exclusively Sunni Muslims” who believe all other Muslims to be impostors or apostates, legitimate targets. You cannot negotiate with these chaps because they want nothing of this world.

I suspect that Aslan knows that this is a rather unoriginal thesis. Most wars are justified as a struggle between good and evil. So he adds an extra layer. In a cosmic war global grievances are fused with local gripes to produce a “master frame”. This is the main tactic of the jihadists. They combine standard Muslim grumbles about Palestine and Kashmir with local issues such as employment and racism to produce a platform for recruitment. Muslims in Britain, for example, are radicalised when they buy in to this potent narrative that portrays them as victims on a world scale and at a national level.

But the thesis breaks down the moment that it is extended beyond the jihadists. Aslan argues that the evangelical Christian zealots in the US and religious Zionists in Israel are also engaged in cosmic wars. Christian zealots want apocalypse now, and work to promote conflict in Palestine, so that they can finally be united with their God in rapture. The religious Zionists, opposed to the secular nationalism upon which Israel was founded, wish to create a theocratic state. Both groups claim that God is on their side; both are zealously acting out an imaginary divine plan. But neither has any local grievances - their master narratives are purely religious.

You don't have to be “exclusively Sunni” to be a jihadist. Before the current crop, most of the jihadists were the Shia revolutionary guards in Iran. Keen on world domination, they try to export their revolution to the Middle East, introducing for the first time the idea of suicide bombing in Lebanon. Being a Shia, Aslan conveniently overlooks the obsession with martyrdom and apocalypse in Shia theology.

The biases in this rather pedestrian book are not only sectarian. Aslan rightly chastises the Bush Administration for giving cosmic dimensions to the “war on terror”. By constructing the enemy as the opposite of us, Satan incarnate, the conflict was moved to a metaphysical plane. Good had to triumph; thus all means become legitimate in this conflict. But, these few shortcomings notwithstanding, the US - unlike Britain - knows how to deal with radical Islam.

It is in the story of Mohammad Siddique Khan, below, one of the July 7, 2005, bombers, that we find the difference in US and British approaches. Khan was radicalised at a particular moment in a particular place. Crossing into Gaza, he saw an old Palestinian man. He was being manhandled by Israeli soldiers. The old man did not speak; he just lowered his head in abject submission while the soldiers rummaged through his belongings. The old man's shame transformed Khan. At that moment he ceased to be British or Pakistani and simply became a Muslim - a member of a community that has been globally humiliated. Khan was able to combine the plight of Palestinians with the problems of alienated young Muslims in Britain to form a single identity - the cause of his radicalisation.

Had Khan been American, Aslan seems to suggest, he would not have been radicalised. Muslims in the US are an integrated, happy and wealthy lot with no local grievances. Their primary sense of identity is not linked to frightened old men in Gaza. That is why there are no home-grown Islamic extremists in the US.

This is patent nonsense. Working-class American Muslims, predominantly taxi drivers, are as alienated as their British counterparts. We do, however, have a more open idea of citizenship in Britain. Far from imposing a single national identity on our citizens we view Britishness as an evolving identity. We do not see criticism of the State as an act of treachery. As Aslan notes, American citizenship is not citizenship but conversion: it involves brainwashing and imposition of a single, fixed nationalistic identity that turns the citizens into patriotic zombies. Uttering a single word against the State is out of the question.

Moreover, unlike the US, Britain is much more open to the outside world. By and large the American media is totally parochial - you are not likely to see what's happening in Gaza through the suffering eyes of the Palestinians. Global issues do not have any impact on American Muslim identity simply because they are not all that aware of global issues. Ignorance is bliss.

Aslan echoes Lincoln's mythic sentiments that the US is the last best hope of mankind. In no other country, he writes, can Muslims “pursue their religion with more freedom and openness than in the United States”. They can, and do, in Britain.

Ziauddin Sardar's latest book is Balti Britain: A Journey Through the British Asian Experience (Granta)

How to Win A Cosmic War: Confronting Radical Islam by Reza Aslan
Heinemann, £18.99; 228pp Buy the book

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