Fundamentalists of all faiths have convinced themselves that militant piety is the only way to save religion from annihilation in an increasingly secularised world. If we are to stand any chance of beating terrorists after the attacks on the United States, we must try to understand their motivation and fears.
This is not a centuries-old phenomenon. Fundamentalism actually began in the US early in the 20th century. Today, it is by no means confined to the Muslim world, but has erupted in every major faith as a reaction against rational, secular modernity. It did not become widespread in the Islamic world until a degree of modernisation had been achieved in the late 1960s, after secular solutions such as nationalism or socialism seemed to have failed.
Wherever a westernised secular state has established itself, a religious fundamentalist movement has developed in conscious rejection. Fundamentalists typically withdraw from mainstream society to create an enclave of pure faith, from the ultra-Orthodox Jewish communities in New York to the training camps of Osama Bin Laden. Surrounded by a world that they perceive as hostile, fundamentalists often plan a counter-offensive, resolved to drag God and religion from the sidelines in secular society and bring them back to centre stage.
In their sacred enclaves, fundamentalists often build a counterculture in conscious opposition. They overemphasise the traditional role of women, for example, because women's emancipation has been a hallmark of modernity. Often, these movements can be seen as the shadow-self of modern society, its distorted mirror image. As a result, many countries find that they are split into hostile camps: those who enjoy and value the ideals of secular humanism, and those who regard it with visceral fear and dread.
This is true of American fundamentalists as well as those in the Middle East. In the US today, about 8 per cent of the population can be described as fundamentalists, but they command widespread support from more conservative Christians in many denominations, as became evident during the rise of the Moral Majority in 1979.
It was American Protestants during the First World War who created the first fundamentalist movement, and who gave us the word "fundamentalist". Their aim was to respond to the liberalisation of their churches by returning to the "fundamentals" of the faith. The word has since been applied to Hindu, Buddhist, Muslim, Jewish, Sikh and even Confucian groups, which resent this Christian nomenclature, since they feel that they have quite different aims. Nevertheless, the term applies to movements that, for all their differences, bear a strong family resemblance.
As the primordial, archetypal fundamentalism, the American case reveals important aspects of this religious rebellion. First, it always begins as an assault on co-religionists, and is directed against foreigners and outsiders only at a later stage. American fundamentalism began as a battle for the control of the Protestant denominations, which were being controlled by more liberal Christians. It remains primarily an intra-Christian conflict.
Islamic fundamentalists initially directed their efforts against their own countrymen. Thus the movement that eventually gave birth to Hamas began as a revolt against the Palestine Liberation Organisation; members were fighting for the Islamic soul of Palestine, and wanted to give the Palestinian struggle a Muslim, rather than a secularist, identity. Israel recognised this and, at first, funded Hamas to undermine the PLO; it was only after the outbreak of the 1987 intifada that Hamas began to target Israelis.
Bin Laden's early offensive was directed against the regime of Saudi Arabia, which, he believed, had corrupted the Islamic ideal. He has also declared a jihad against the secularist governments of Egypt, Syria and Jordan, and against the Shi'ite government of Iran. He now wishes to eliminate the American presence from the Middle East because he sees it as the root cause of this widespread defection from the purity of Islam. The fundamentalist battle is not primarily directed against either Israel or the west per se; it is an intra-societal struggle.
Fundamentalism always begins as a response to what is experienced as an assault by the liberal or secular world. The American fundamentalist movement began in earnest in 1917, after liberal Christians mounted an attack against their more conservative brethren, accusing them of undermining the war effort and of being in league with the Germans. The fundamentalists believed that the End of Days was nigh; they condemned democracy as mob rule, and saw the League of Nations as the abode of Antichrist. To this day, American fundamentalists are at best highly suspicious of democracy, and they regard the United Nations, the European Union and the World Council of Churches as satanic.
Those in the Middle East have also experienced modernity as evil and aggressive, and it's hardly surprising if they do not regard secularism as benign. When Ataturk began to secularise Turkey, he closed down all the madrasahs and forced the Sufi organisations underground.
In 1935, Shah Reza Pahlavi gave his soldiers orders to fire at unarmed demonstrators who were peacefully protesting against obligatory western dress in one of the holiest shrines in Iran: hundreds of Iranians died. Later, Iranian Shi'ite fundamentalism was born as a result of the aggressive secularism of Shah Muhammad Reza.
The type of Sunni fundamentalism loosely espoused by Osama Bin Laden was born in the concentration camps in which President Gamal Abdel Nasser had incarcerated Muslim activists, many of whom had done nothing more incriminating than handing out leaflets. Today, Muslims cite the bombing of Iraq, the death of thousands of Iraqi civilians after the Gulf war, and the destruction of Palestinian homes by American shells as the reason for this latest fundamentalist offensive against the US.
Americans have not resorted to the same degree of violence as Islamic fundamentalists because the attacks on them have been far less extreme. But they inveigh against the "secular humanism" of the federal government in language that often seems as paranoid as that used by their Muslim counterparts against America or Israel. In small-town America, people feel almost as "colonised" by the alien ethos of Yale, Harvard and Washington as do some of the inhabitants of Muslim countries.
The American experience also suggests that, when it is attacked, fundamentalism becomes more extreme. Before the Scopes trial of 1925, when Protestant fundamentalists tried to ban the teaching of evolution in schools, many fundamentalists had tended towards the left of the political spectrum. After the Scopes trial, when the fundamentalists were so ridiculed by the secular press that they seemed to suffer death by media, they swung to the far right and became much more militantly literal in their religious views.
Fundamentalism is becoming more extreme in the US, as well as in the Middle East. New American religious radicals now regard the Moral Majority as far too moderate; some are developing forms of Christian fascism. The most frightening of these movements is the network known as Christian Identity, which looks forward to the demise of the federal government. It is viciously racist, and it almost certainly influenced Timothy McVeigh, who bombed the federal building in Oklahoma in 1994.
Crackdowns and suppression will only make matters worse, because fundamentalism is rooted in a profound fear of annihilation. Every fundamentalist movement I have studied in Judaism, Christianity and Islam is convinced that secular society is determined to wipe out religion. In the US, extremists fear an insidious corruption of Godly America by books that promote a liberal or scientific ideal, or by the promotion of feminism, which they regard with horror.
Fears of extinction in Muslim countries centre on the military might of Israel and the Pentagon. When people believe they are fighting for survival, they will often lash out violently - but also in a nihilistic way. In their fear for the future of religion, fundamentalists of all hues distort the message of their scriptures, playing down the compassionate ethos of, for example, the Bible or the Koran. Bad religion, as we saw on 11 September, can result in actions that are wholly evil.
While the vast majority of fundamentalists do not commit acts of terror, many cultivate violent theologies. American fundamentalists envisage an imminent End of Days, in which God will smash this wicked secular world and submerge its inhabitants in a tide of bloodshed. The collapse of the World Trade Centre bore a strong resemblance to this apocalyptic vision.
In Britain, we do not express our disquiet in religious terms, but the desire to belong to a clearly defined group, the sense of lost prestige, the pent-up rage and frustration that we see in our football hooliganism show the same brew of emotions. This profound disaffection, wherever it occurs, indicates anxiety, anger and resentment that, as we have seen, no society can safely ignore.
Karen Armstrong is the author of The Battle for God: fundamentalism in Judaism, Christianity and Islam (Harper Collins, £9.99)