It was not a one-off, then. After the bombs exploded on 7/7, it was possible to think that they were the dying gasp of a decreasingly lethal form of terrorism. The death toll from successive attacks attributed to al-Qa'ida groups declined from 3,000 in New York, Washington and Pennsylvania, to 202 in Bali, 191 in Madrid, and 52 in London.
But the significance of the London bombings, last week's weird replay as tragi-farce, and yesterday's bombing of Sharm el Sheikh, must be that we are not in the middle of the struggle against jihadist terrorism, let alone near the end. It is all too likely that the phenomenon is only just beginning. All the more important, therefore, that we redouble our efforts to understand where it comes from. As John Howard, the Australian prime minister, drily put it on Thursday: "You can't put yourself in the mind of a successful suicide bomber." Yet we already know more than we might have wanted to know, in other times, about such a bomber's background and psychology.
This is not a problem of Islam. As Imran Khan points out on this page, neither terrorism nor the use of suicide is unique to that religion. The Japanese kamikaze pilots were shintoists - admittedly they flew against military targets, but reclassifying civilians as combatants is easy enough for fanatics. The Tamil Tigers use suicide terrorism too, and they are Hindus. So the problem is not intrinsic to one religion; yet the origin of the current threat lies in the psychology and culture of a group that defines itself by its adherence to a religion.
A Muslim friend of mine in the East End of London says that the sense of victimisation and injustice goes so deep among his fellow religionists that he sometimes despairs. "This all goes back to the burning of The Satanic Verses," he says. It was in 1988 that we should have realised that we were up against a culture - he doesn't like the term "Muslim community" - that tended to irrationalism and self-pity. Salman Rushdie did not create that culture, but he provided a focus for it and fed its sense of grievance.
The Iraq issue serves much the same purpose today. Seventeen years ago, there were appeasers who said that Rushdie should apologise to all Muslims in the world for the offence he had caused and that his publishers should cease distribution of the book. Today we are told that Tony Blair should admit that the Iraq war has made Britain more of a target, instead of insisting that it should not have done so. My Muslim friend opposed the war, but says that, after the London bombings, he felt like shaking some of his co-religionists and saying: "Get a grip. Just be quiet for five seconds and empathise."
Of course, the jihadist terrorists are not typical of British Muslims. But neither is their world view completely aberrant. Theirs is a distilled form of the idea of victimhood that is common among Muslims around the world. A concentrated form of a collective victimhood is what jihadist suicide bombers have in common with other terrorists such as the IRA, Eta, the Tamil Tigers, the Red Army Faction and Timothy McVeigh. They see themselves as members of a persecuted group with no choice but to resort to extreme methods to fight back against oppression by more powerful forces.
The concept of the Muslim umma or international brotherhood is central to the sense of grievance. It unites Palestine, Chechnya, Kashmir, Afghanistan and Iraq in one seamless story of global persecution of Muslims. The super-strength version adds in East Timor (which won independence from Muslim Indonesia through international pressure in 1999) and goes back to the Crusades and the Christian reconquest of Spain in the 15th century. First you start on the weaker brew, variants of which are quite normal among Muslims, but which acts for a tiny minority as a gateway drug to the harder stuff.
It ought to be obvious, however, that even the diluted version of the persecution myth is nonsense. It overlooks the fact that the democratic Muslim government of Afghanistan replaced the Taliban dictatorship with the support of nearly all Muslim countries. It ignores the fact that most of the casualties in Iraq now are Muslims killing Muslims. And it is silent about the US-led interventions in Bosnia and Kosovo that defended Muslims against the threat of genocide.
For the tiny minority, this web of half-truths and evasions leads to the murderous ideology of suicide terrorism. According to a survey of British Muslims carried out last week by Communicate Research, only 2 per cent of them agree with what the suicide bombers of 7 July did. But that still suggests that 30,000 people in this country support such terrorism. Even if we halve that figure to allow for the few respondents who purposely give "shocking" answers to poll questions, there is a large pool of potential recruits from which the bombers of the future could be drawn.
So what is to be done? My East End Muslim friend sighs. He challenges the wilder views of fellow Muslims when he can. When respectable bankers or lawyers tell him that the Islamic caliphate - for which the Taliban was the closest model - would have to be self-sufficient to prevent the US exerting economic influence on its domestic policy, he asks why Islam should be so unable to resist the free exchange of ideas. One thing that non-Muslims could do is to avoid reinforcing Muslim myths with ones of their own. There is an unfortunate coincidence between the Muslim persecution myth and the anti-American myths of some of the British left. Palestine and Iraq are conflated as a tale of US imperialism in the Middle East, with Afghanistan increasingly dragged in as a US puppet state - despite an 80 per cent turnout in October's election that produced a decisive democratic mandate for President Hamid Karzai. And the idea that Iraqis are "resisting" oppressive occupying forces flies in the face of evidence that most Iraqis look forward to an independent, democratic future. Leave aside for now how US imperialism is supposed to be responsible for the oppression of Chechnya and the partition of Kashmir.
The worst succour that the anti-war left in Britain can give to the terrorists, however, is to entertain the idea that there is a moral equivalence between the deliberate killing of civilians and the casualties of military action in Iraq. Of course, people who think the war was unjustified feel passionately about civilian deaths. But let us get two things straight. First, even Iraq Body Count, an anti-war campaign, puts the total attributable to coalition forces at under 10,000, rather than the figure with an extra zero that is the common misconception of anti-war propaganda. And second, the purpose of the invasion of Iraq, whatever you think of George Bush's motives, was not to kill civilians. Even on the strongest anti-war reading, there is a vast moral gulf between the actions of the coalition and those of suicide bombers, whether in London, Iraq or Israel.
The myths that feed terrorism have to be challenged, by Muslims such as my friend, and by non-Muslims too.Reuse content