If I had been 'S', I'd have been tempted to say to the planner, 'Well, in that case, why don't you put your neck where your mouth is? Why don't you do the suicide mission and take the fast track to Paradise?' But what is so hard for us to understand is that — to repeat the point because it is so important — these people actually believe what they say they believe. The take-home message is that we should blame religion itself, not religious extremism — as though that were some kind of terrible perversion of real, decent religion. Voltaire got it right long ago: 'Those who can make you believe absurdities can make you commit atrocities.' So did Bertrand Russell: 'Many people would sooner die than think. In fact they do.'

As long as we accept the principle that religious faith must be respected simply because it is religious faith, it is hard to withhold respect from the faith of Osama bin Laden and the suicide bombers. The alternative, one so transparent that it should need no urging, is to abandon the principle of automatic respect for religious faith. This is one reason why I do everything in my power to warn people against faith itself, not just against so-called 'extremist' faith. The teachings of 'moderate' religion, though not extremist in themselves, are an open invitation to extremism.

It might be said that there is nothing special about religious faith here. Patriotic love of country or ethnic group can also make the world safe for its own version of extremism, can't it? Yes it can, as with the kamikazes in Japan and the Tamil Tigers in Sri Lanka. But religious faith is an especially potent silencer of rational calculation, which usually seems to trump all others. This is mostly, I suspect, because of the easy and beguiling promise that death is not the end, and that a martyr's heaven is especially glorious. But it is also partly because it discourages questioning, by its very nature.

Christianity, just as much as Islam, teaches children that unquestioned faith is a virtue. You don't have to make the case for what you believe. If somebody announces that it is part of his faith, the rest of society, whether of the same faith, or another, or of none, is obliged, by ingrained custom, to 'respect' it without question; respect it until the day it manifests itself in a horrible massacre like the destruction of the World Trade Center, or the London or Madrid bombings. Then there is a great chorus of disownings, as clerics and 'community leaders' (who elected them, by the way?) line up to explain that this extremism is a perversion of the 'true' faith. But how can there be a perversion of faith, if faith, lacking objective justification, doesn't have any demonstrable standard to pervert?

Ten years ago, Ibn Warraq, in his excellent book Why I Am Not a Muslim, made a similar point from the standpoint of a deeply knowledgeable scholar of Islam. Indeed, a good alternative title for Warraq's book might have been The Myth of Moderate Islam, which is the actual title of a more recent article in the (London) Spectator (30 July 2005) by another scholar, Patrick Sookhdeo, director of the Institute for the Study of Islam and Christianity. 'By far the majority of Muslims today live their lives without recourse to violence, for the Koran is like a pick-and-mix selection. If you want peace, you can find peaceable verses. If you want war, you can find bellicose verses.'

Sookhdeo goes on to explain how Islamic scholars, in order to cope with the many contradictions that they found in the Qur'an, developed the principle of abrogation, whereby later texts trump earlier ones. Unfortunately, the peaceable passages in the Qur'an are mostly early, dating from Muhammad's time in Mecca. The more belligerent verses tend to date from later, after his flight to Medina. The result is that

More generally (and this applies to Christianity no less than to Islam), what is really pernicious is the practice of teaching children that faith itself is a virtue. Faith is an evil precisely because it requires no justification and brooks no argument. Teaching children that unquestioned faith is a virtue primes them — given certain other ingredients that are not hard to come by — to grow up into potentially lethal weapons for future jihads or crusades. Immunized against fear by the promise of a martyr's paradise, the authentic faith-head deserves a high place in the history of armaments, alongside the longbow, the warhorse, the tank and the cluster bomb. If children were taught to question and think through their beliefs, instead of being taught the superior virtue of faith without question, it is a good bet that there would be no suicide bombers. Suicide bombers do what they do because they really believe what they were taught in their religious schools: that duty to God exceeds all other priorities, and that martyrdom in his service will be rewarded in the gardens of Paradise. And they were taught that lesson not necessarily by extremist fanatics but by decent, gentle, mainstream religious instructors, who lined them up in their madrasas, sitting in rows, rhythmically nodding their innocent little heads up and down while they learned every word of the holy book like demented parrots. Faith can be very very dangerous, and deliberately to implant it into the vulnerable mind of an innocent child is a grievous wrong. It is to childhood itself, and the violation of childhood by religion, that we turn in the next chapter.

I begin with an anecdote of nineteenth-century Italy. I am not implying that anything like this awful story could happen today. But the attitudes of mind that it betrays are lamentably current, even though the practical details are not. This nineteenth-century human tragedy sheds a pitiless light on present-day religious attitudes to children.

In 1858 Edgardo Mortara, a six-year-old child of Jewish parents living in Bologna, was legally seized by the papal police acting under orders from the Inquisition. Edgardo was forcibly dragged away from his weeping mother and distraught father to the Catechumens (house for the conversion of Jews and Muslims) in Rome, and thereafter brought up as a Roman Catholic. Aside from occasional brief visits under close priestly supervision, his parents never saw him again. The story is told by David I. Kertzer in his remarkable book, The Kidnapping of Edgardo Mortara.

Edgardo's story was by no means unusual in Italy at the time, and the reason for these priestly abductions was always the same. In every case, the child had been secretly baptized at some earlier date, usually by a Catholic nursemaid, and the Inquisition later came to hear of the baptism. It was a central part of the Roman Catholic belief-system that, once a child had been baptized, however informally and clandestinely, that child was irrevocably transformed into a Christian. In their mental world, to allow a 'Christian child' to stay with his Jewish parents was not an option, and they maintained this bizarre and cruel stance steadfastly, and with the utmost sincerity, in the face of worldwide outrage. That widespread outrage, by the way, was dismissed by the Catholic newspaper Civilta Cattolica as due to the international power of rich Jews — sounds familiar, doesn't it?