THE FERTILE PLAIN between the Tigris and Euphrates rivers could not be more different than the mountains of central Bosnia. Here farmers in small villages hidden beneath a canopy of palm trees exist much as they have since Ancient Mesopotamia. Canals criss-cross the landscape irrigating the land from the waters of the two great rivers. Where modern urban Iraq is dirty, ugly and threatening, in the countryside there is a timeless quality which suggests that these simple villagers may have escaped the mayhem gripping the rest of the country.

But as Yusuf Shaalan explains, first appearances can be very deceptive. Short, bright-eyed and plain-speaking, Yusuf’s story could have come straight from an account of the ethnic cleansing that swept the Balkans a decade ago. After his two brothers were killed last year, the farmer knew that the Sunni gunmen would be coming for him. At five o’clock one morning he woke to find his home on fire and managed to get his family out and flee his village near Madaen, south of Baghdad.

“Everything I had was destroyed,” he said in Baghdad, where he and dozens of other Shia Muslim families from the area are living as refugees in the Shia slum known as Sadr City. “I know the people who did it. I grew up with them. I went to school with them. We had always got on fine. But now this sectarian feeling has gripped the community. I think there will be a civil war.”

Sectarianism is nothing new in Iraq, the birthplace of the Shia branch of Islam. There have always been tensions between Shia and Sunni Muslims here and even greater strains with the ethnically distinct Kurds in the north. But as most Iraqis proudly declare when the subject is raised, they are Iraqis first and have a strong sense of their national identity. To defend this argument they cite the bloodiest battles of the Iran-Iraq war, when Shia foot soldiers fought their Iranian brethren to a standstill in the trenches of southern Iraq’s marshes.

Unlike Lebanon and Bosnia, where sectarian divisions erupted into full-scale civil wars, after two years of a violent insurgency Iraq has still not followed that path. The Shias, who now head the newly elected government, have been attacked daily by Sunni extremists. They want to inflame sectarian passions in the hope of provoking a civil war and making this country even more violent and chaotic than it is now. So far, everyone seems to agree, they have failed.

But what happened at Madaen, where the bodies of hundreds of Shia victims were pulled out of the river in April, could be a pivotal point in the history of post-Saddam Iraq. A swath of Shia villages has been ethnically cleansed and there is evidence that the Shias are fighting back. Several Sunni clerics have been abducted by men wearing police uniforms and their bodies later dumped near Sadr city. This has led to calls for the resignation of Bayan Jabbor, the new Minister of the Interior. He is closely connected to one of the main Shia militias, whose men are increasingly filling the ranks of the security forces.

What I find more disturbing than this cycle of tit-for-tat violence is the very strong sense that ordinary Iraqis are for the first time being infected by the sectarian bug. Western correspondents in Baghdad rely heavily on local staff for reporting. Even a few months ago it did not matter whom you sent on an assignment. Shias and Sunnis felt free to travel the country and speak to representatives of all communities. Now Sunni reporters insist on covering only Sunni areas and Sunni issues, and the same applies for the Shias. When a reporter returns with details of the latest sectarian outrage, there is a distinct tension in the office between the two sides.

This is repeated across society. Baghdad University has always been one of the few havens in the capital where young people from every background have managed to coexist peacefully. But the calm was shattered recently when Masar Sarhan, a Shia student, was murdered after he threw a party to celebrate the election of the new Government. The killing sparked unrest on the campus and some Sunni professors are too afraid to return.

The paranoia in the Sunni community is palpable. For centuries the ruling class in Iraq, they were swept aside by the US-led invasion and are now a vulnerable and angry minority. Few will openly criticise the insurgency, in spite of its brutal methods. The Americans, who still dominate politics in Iraq, remain adamant that civil war is still only a remote possibility and that everyone who matters is committed to putting “the genie back in the bottle”. Sunni leaders recently formed a new group dedicated to co-operating with the Shia Government on drawing up a new constitution. Even rabble-rousers such as Moqtadr al-Sadr, the Shia cleric who led a failed uprising last year, are now mediating between the two sides. Every political and religious leader is appealing for restraint.

“They (the Sunnis and Shias) have peered over the edge and they do not like what they see,” said an American diplomat in Baghdad. “Now people are pulling back.”

The consequences of a Balkans-style civil war fought between the two heavily armed communities are too hideous to imagine. It would dwarf the present fighting in Iraq, where some 700 Iraqis have been killed over the past four weeks. Sunnis and Shias are not neatly divided. There are many mixed marriages and the communities live side by side across large areas of central Iraq, in villages and towns and particularly in Baghdad, where they are evenly split among the six million inhabitants.

Everyone is hoping that Yusuf, the refugee farmer, is dead wrong.

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