The sight of millions of Iraqi pilgrims flocking to the holy Shia city of Kerbala has caused disquiet in Washington. Since Shias comprise about 60% of the population of Iraq, it is not inconceivable that the ousting of Saddam Hussein could result in a democratically elected Shia government - a nightmare scenario to many in the west, where Shi'ism has been regarded as the epitome of fanaticism since the Iranian revolution of 1978-79. Among many the mention of Shi'ism immediately evokes thoughts of sinister ayatollahs, processions of flagellants, and an implacable hostility to progress and democracy. But how accurate is our perception of the Shia, and would a Shia Iraq necessarily be a disaster?

Unlike the governments of Europe and America, Iraqi Shias have consistently and heroically opposed Saddam. During the 70s and 80s, while we in the west seemed to find the Ba'ath regime quite acceptable, the Shias of Iraq regularly risked their lives in the arba'in pilgrimage, a three-day march from Najaf to Kerbala, braving police bullets, waving the bloodstained shirts of those who had fallen, and shouting: "Oh Saddam, take your hands off the army! The people do not want you!" It was not Saddam's secularist policies, his initial courting of the west, nor his neglect of Islamic law that principally offended them. Their resistance to Baghdad was fuelled by a visceral and religiously inspired rejection of tyranny.

The shrine cities of Najaf and Kerbala take us to the heart of Shi'ism. Najaf contains the tomb of the Prophet Mohammed's cousin and son-in-law, Ali bin Abi Talib, the fourth caliph of Islam, who was murdered in 661. After his death, Islam was never the same. Ali had been a devout Muslim and had an outstanding reputation for justice, but the Umayyad dynasty that followed him was increasingly worldly, inegalitarian and autocratic. To many this seemed a betrayal of the Koran, which insisted that the first duty of Muslims was to create a just and equal society. Malcontents who called themselves the Shia i-Ali (Ali's partisans) developed a piety of protest, refused to accept the Umayyad caliphs, and regarded Ali's descendants as the true leaders of the Muslim community.

In 680, the Shias of Kufa in Iraq called for the rule of Ali's son, Husain. Even though the caliph, Yazid, quashed this uprising, Husain set out for Iraq with a small band of relatives, convinced that the spectacle of the Prophet's family, marching to confront the caliph, would remind the regime of its social responsibility. But Yazid dispatched his army, which slaughtered Husain and his followers on the plain of Kerbala. Husain was the last to die, holding his infant son in his arms.

For Shias the tragedy is a symbol of the chronic injustice that pervades human life. To this day, Shias can feel as spiritually violated by cruel or despotic rule as a Christian who hears the Bible insulted or sees the Eucharistic host profaned. This passion informed the Iranian revolution, which many experienced as a re-enactment of Kerbala - with the shah cast as a latter-day Yazid - as well as the Iraqi arba'in to Kerbala.

Shi'ism has always had revolutionary potential, but the Kerbala paradigm also inspired what one might call a religiously motivated secularism. Long before western philosophers called for the separation of church and state, Shias had privatised faith, convinced that it was impossible to integrate the religious imperative with the grim world of politics that seemed murderously antagonistic to it. This insight was borne out by the tragic fate of all the Shia imams, the descendants of Ali: every single one was imprisoned, exiled or executed by the caliphs, who could not tolerate this principled challenge to their rule. By the eighth century, most Shias held aloof from politics, concentrated on the mystical interpretation of scripture, and regarded any government - even one that was avowedly Islamic - as illegitimate.

The separation of religion and politics remains deeply embedded in the Shia psyche. It springs not simply from malaise, but from a divine discontent with the state of the Muslim community. Even in Iran, which became a Shia country in the early 16th century, the ulama (the religious scholars) refused public office, adopted an oppositional stance to the state, and formed an alternative establishment that - implicitly or explicitly - challenged the shahs on behalf of the people.

In his opposition to Shah Reza Pahlavi's brutal dictatorship, Ayatollah Khomeini was thus a typical figure, though in declaring that a mullah should be head of state he was breaking with centuries of sacred Shia tradition. Yet at the end of his life, even Khomeini insisted that government must be emancipated from the constraining laws of traditional religion. The experience of running a modern state had convinced him of the wisdom of Shia "secularism".

It would be a mistake to imagine that Shias are reflexively opposed to modern, western ideals. In 1906, leading mullahs in Iran campaigned alongside secularist intellectuals for a modern constitution on European lines, and parliamentary rule. Because representative government would limit the tyranny of the shahs, it was a project worthy of the Shia. Today, 25 years after the revolution, Iran has moved beyond Khomeini. It has a freer press than any of its Arab neighbours. The conservative clerics whose ideas were forged in the 1950s seem increasingly irrelevant to the young, who want Iran to remain a religious country, and are proud to be Shia, but support President Khatami in his demand for greater democracy. Abdolkarim Sorush, the chief intellectual of Iran, argues that every Iranian has three identities: Shia, Persian and western.

The US administration has recently spoken darkly of Iranian "agents" infiltrating Iraq to spread revolutionary Islam. One of the Shia movements in Iraq, the Supreme Assembly for the Islamic Revolution, was indeed founded in Tehran in 1982 as an umbrella organisation for all Iraqi Shia opposition groups. But it never fulfilled this function, since Iraqi Shias resist Iranian control. Today Iraqi clerics, who were in exile in Iran, are now returning home. They have had enough of Iranian-style theocracy, and are reverting to traditional Shia "secularism".

Hizb al-Da'wa al-Islamiyya, the other main Iraqi Shia movement, has always operated independently of Iran, has a modern organisation and a strong lay membership. In the past, Da'wa has asserted that if it is elected, it will not impose Islamic law against the will of the people, and that it wants a liberal democracy, a multiparty system, modern education, free elections and a free press. Like any religious tradition, Shi'ism has had its share of belligerent, narrow-minded hardliners, but from the very beginning, leading Shia thinkers promoted ideals that are familiar to us in the west, not least that criticism of their own society is the basis of the democratic ethos. After decades of Saddam, western-style secularism may not appeal to many Iraqis, and Shia leaders, who have so bravely opposed the Ba'ath regime, are likely to be more respected than an Iraqi exile parachuted in by the Americans. If Iraqis choose a Shia government in free and fair elections, we should at least give it the benefit of the doubt.

Karen Armstrong is the author of Islam: A Short History (Weidenfeld) and The Battle for God: A History of Fundamentalism (HarperCollins).

Source: Guardian