Tens of thousands of Shiite Muslims march in Baghdad carrying portraits of Grand Ayatollah Ali al-Husseini al-Sistani and other Shiite clerics. The fall of Saddam Hussein gave Iraq's Shia majority its first real taste of political power. (Muhammed Muheisen/Associated Press)

The schism that rends the Islamic faith has its origins in centuries-old theology, but modern politics and demographics keep it alive and well across the Middle East.

Shia Muslims are a minority in global Islam, often shunned or despised by conservative Sunnis, but they are an active and increasingly influential community in several key regions and countries. That activism is worrying Sunni leaders and Washington, which has long had troubled relations with Shia governments and groups.

King Abdullah of Jordan warned last year that Iran's oil wealth and regional influence could lead to a "Shia crescent" across the Middle East that posed security and religious challenges. The Iranian-born American scholar, Vali Nasr, raised eyebrows and fears in the U.S. recently with an essay in Foreign Affairs magazine "When the Shi'ites Rise."

From Iran to Lebanon, Bahrain to eastern Saudi Arabia's oilfields, the growing power of Shia Muslims is prompting interest, concern, and occasionally violence or repression by Sunnis. In part, it's because Iran is awash with petro-dollars from high oil prices. That enables Tehran to fund and arm groups like Hezbollah in Lebanon, and to send humanitarian aid to Shia communities hit by poverty or the effects of war.

Iran is also reaping the benefits of two military actions launched by its arch-enemy, the United States. The toppling of the Taliban in Afghanistan and Saddam Hussein's regime in Baghdad have removed two neighbouring Sunni regimes that helped check Tehran's regional ambitions. Iraq's Shia majority is taking up a long-denied mantle, political dominance in its own country, and Iran is firmly behind its co-religionists in every sense.

Shia Muslim devotees in Afghanistan whipping themselves with metal flails at Moharram, a grief-ridden festival that marks the martyrdom of Hussein, grandson of the Prophet of Mohammed, and one of the acknowledged founders of the Shia tradition. (Rafiq Maqbool/Associated Press)

Sectarian relations a sensitive issue

Washington had hoped a Shia-led government in Baghdad would be a natural ally in the region, but Iraqi administrations so far have been far closer to Tehran than U.S. planners would like. Nor are Iraq's security forces anywhere near being capable of offsetting Iranian military prowess and the sheer size of its standing army, by far the largest in the Middle East.

What's most troubling to Sunni-led regimes is the effect of Iran's resurgence on their own often repressed and occasionally restive Shia populations. So sensitive is the issue of sectarian relations in some Muslim countries that Shias aren't even counted as being from a separate religious tradition. Saudi Arabia and other Persian Gulf states do not even keep statistics about the number of Shias within their borders.

The tiny island nation of Bahrain is on the frontline of Shia-Sunni political confrontation in the Gulf. Rich in natural gas and probably the most democratic Arab country, Bahrain has a Shia majority but a Sunni governing elite. Violent confrontations between the communities in the past have given way to electoral politics that is still confrontational and fractious, but largely peaceful. Bahrain's ruling al-Khalifa family started the democratization project and appears committed to maintaining it, but Iranian influence and political ambitions are still feared.

Saudi Arabia's Shia population officially doesn't exist. The government in Riyadh says simply that Saudi Arabia is 100 per cent Muslim. In effect, that means Sunni because the assumption of many influential Saudi clergymen is that Shias are either apostate or not Islamic enough to be considered Muslims. But in the oil-rich eastern provinces of the kingdom, hundreds of thousands of Shias are restive and concerned about their second-class status. They are among the most enthusiastic participants in recent municipal elections in Saudi Arabia, but many Shia want far more than they're getting from the secretive, often repressive and sectarian Saudi system of government.

In Pakistan and Afghanistan, Shia minorities exist uneasily alongside large Sunni majorities. Sunni extremists, often aligned with al-Qaeda or the Taliban, have attacked Shia mosques and other targets, prompting retaliation. Afghanistan's Shia are a visibly distinct ethnic group who are routinely discriminated against by most of the country's Sunni factions. In both countries, Iranian-influenced Shia assertiveness is having an impact on religious and communal attitudes.)

Critics recommend regional role of U.S. in Mideast

Perceptions of Iran's regional and pan-Shia ambitions have prompted the administration of U.S. President George W. Bush to alter some of its Middle East policies, according to media reports and analysts. Washington takes Sunni concerns about Iran seriously, and has supported efforts by Saudi and Jordanian officials to contain Hezbollah in Lebanon. Critics of this approach say this is a risky strategy, and recommend instead that the U.S. talk to Iran about a more constructive regional role in the Middle East.

The respected commentator, Michael Young, of the Daily Star newspaper in Beirut, recently warned of the dangers of festering sectarian hostilities between the two traditions of Islam.

"Once opened, the floodgates of Sunni-Shiite antagonism could become a Leviathan," Young wrote in the Wall Street Journal, "...sweeping away the fragile reality on the ground. Even in societies where Sunnis and Shiites now peacefully co-exist, sectarian discord would become the norm."

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