Hussein Hashimi has a CD-ROM full of pictures of the dead. For the last two months, the young Shiite says, Sunni extremists rampaged through his hometown of Madaen. They torched the local police stations, abducted dozens of members of the local Shiite minority, burned down the mosque and killed not only the imam but his 8-year-old son. Many Shiite families fled; others barricaded themselves in their homes. Last week Iraqi security forces finally came in and restored order. Hashimi has lists of the missing and of the dead who have been identified. He has the names of the alleged perpetrators and a map showing the home of the Sunni he accuses of being responsible for the atrocities.

So is Hashimi fighting back? Not at all. "We just ran away," he says without a trace of embarrassment. "Sistani and the religious authorities in Najaf decided not to use force, so we couldn't do anything." To the Shiites of Iraq, Grand Ayatollah Ali Sistani's word is law. "We must obey."

Their obedience was tested yet again last week--and again it held firm. In Madaen and villages nearby, corpses bobbed to the surface of the Tigris River until police counted 60. Hashimi and his friends photographed 55 of the bodies and delivered the pictures and lists to Baghdad. Shiite politicians accused the insurgents of ethnic cleansing, and demanded that the caretaker government act. Insurgents in another town near Baghdad, Haditha, responded by kidnapping 19 Shiite fishermen and National Guardsmen, lining them up against a wall in a sports stadium and shooting them dead. Then, during Friday prayers, a suicide car bomber in east Baghdad hit the Shia Al Subeih mosque, killing nine and wounding 20.

In some parts of the world, any one of those incidents would likely have led to a retaliatory bloodbath. But there wasn't a single verifiable incident of a counterstrike from the Shiites of Iraq. One of Sistani's fellow ayatollahs, Mohammed Kadhim al-Haeri, issued a warning to the faithful: "Beware of the witty Saddamites and their followers, Sunnis. Be patient and wise. Beware of sectarian war." His people clearly listened. "If it were not for the wisdom of the Shia leaders, who can control their people, there would have been the probability of civil war," says Jawad Maliky, spokesman for one of Iraq's two leading Shia political parties, the Dawa.

If the leaders' wisdom prevails, Iraq's Shia will have their first elected majority government in the history of any Arab country. Sunni Arab extremists may have no way to prevent it other than by provoking a civil war--and the Shia aren't playing. "You can rule out the insurgents taking over the country," says a Western diplomat. "That's just never going to happen." The Shia and their Kurdish allies constitute 80 percent of the population. Only a sectarian civil war could change everything for the insurgents. "They want to force the Shia to retaliate, so they can create Sunni Arab pockets they can control, but there must be a Shia reaction for that to happen," says Hussein Shahristani, a Shia leader and vice-chairman of the National Assembly. "But this is a last resort. The insurgency is losing ground."

The Shia have already withstood outrages far worse than last week's. Since Baghdad fell, two of their ayatollahs have been assassinated, one in a suicide truck bombing that killed 94 of the cleric's followers. Responsibility for that attack was claimed by the venomously anti-Shiite terrorist leader Abu Mussab al-Zarqawi, leader of the country's branch of Al Qaeda. At the annual Ashoura festival this past February, no fewer than 10 suicide car bombers killed 74 pilgrims and worshippers. "I was nearby when it happened," says Shahristani, "and I was really amazed when these simple, common people began to demonstrate for Islamic unity. But it has taken the Sunnis a bit too long to realize the Shia want to live among them as brothers." Assassins have killed some of Sistani's senior aides and representatives, too, but he has never wavered from his calls for restraint.

Still, everyone's patience has limits. "Our people will not keep silent for long," warned the Najaf governor, Asad Abu Gulal, at a funeral for the mosque bombing victims. Some Shiite politicians see a danger that Iraq's failure to form a new government could prove too much. Iraq's caretaker government, led by the American-appointed interim Prime Minister Iyad Allawi, is barely functioning. "It's a dangerous game," said the new vice president, Sheikh Ghazi al Yawer, one of the incoming government's few Sunni politicians. "This caretaker government must come to an end." American diplomats and generals, unworried until a few weeks ago, have become alarmed at the ongoing delay. "We can't get anything done," said one American official. "This is no way to fight a war." Even Allawi is fed up with the Assembly members' wrangling. "Sistani should issue a fatwa telling them to get their act together," he told NEWSWEEK.

It's not as easy as it sounds, though. The Transitional Administrative Law, crafted by U.S. and U.N. negotiators along with Iraqi politicians, established a complex set of checks and balances to prevent any one sectarian group from dominating the government. Forming a new government requires a two-thirds majority, which means that its shape is dictated not only by the Assembly's Shia majority but also by the second-largest bloc, the Kurdish parties. Dawa politician Ibrahim Jaafari was named prime minister on April 7, but 31 cabinet positions are still being hotly debated. In an interview with NEWSWEEK last Thursday, Jaafari confidently asserted that he expected a government by the end of the day. "We did our best so that the role of our brothers the Sunnis in the cabinet would be noticeable and strong," he said. Even so, the week ended with the deadlock still unresolved.

The basic plan seemed straightforward enough. The Shiites and the Kurds would divvy the cabinet seats according to their relative populations; then each would voluntarily cede a couple of ministries to the Sunnis, who had chosen to boycott the elections and thus are underrepresented in the Assembly. Sistani, eager to persuade Sunnis that their future lies with the government rather than with the insurgency, insisted that Shiite leaders give them prominent political roles. The Kurds offered to kick in an extra ministry, if the Shiites would match that by giving up two more positions, but Jaafari couldn't get his party's various factions to accept such a sacrifice. In the end they offered the Sunnis only four cabinet posts, and the deal collapsed. Still, some of the Assembly members were practically giddy at the prospect of democracy in action. "A Kurdish filibuster," one Kurdish politician marvels. "This is exhilarating." His mood quickly turns serious. "We are at the peak of our influence. But if we push too far we could lose."

Even thornier was the decision to give the Defense Ministry to the Sunnis. The thought infuriated Shiite hard-liners. Dawa and the Shiites' other major religious party, SCIRI, have been particularly vocal about their desire to ferret out Baathist infiltrators in the government. Sunni politicians feared that any such effort would become a full-blown purge. They were already complaining that some ministries in the interim government had become almost exclusively Shiite enclaves, and they predicted that a Sunni minister of Defense would be no more than a figurehead, wielding no real control. "The Shia want to have a token Sunni under their thumb in Defense," one Sunni politician said.

Madaen is now at the center of the two sides' dispute over the security services. As Hashimi's story flashed through Baghdad from one teller to the next, it metastasized into a wild account of 50, 75 or 150 Shiites, men, women and children being taken hostage. Shiite politicians charged that insurgents in Madaen were brazenly abducting Shiites in broad daylight from the streets. But after security forces gained control of the town, Iraq's Interior minister, Falah Naqib (a Sunni), announced that no hostages had been found. In response, some Shiites argued that the failure to find hostages merely proved the longstanding contention of Naqib's critics that his ministry is riddled with infiltrators. Sunni politicians retaliated with their own wild allegation that the Madaen's real "abductees" were Sunnis who had been rounded up by local police and jailed incommunicado.

The facts are scarcely less chilling than the rumors. According to local police, as well as reports from Iraqi journalists who reached Madaen, most of the corpses were unidentified young men who had been killed elsewhere and dumped in the river. Iraqi police said the victims who could be identified came from cities and villages up and down the Tigris valley, particularly from towns astride the highways that connect Baghdad to the south. Those roads, sometimes known as the throat of Baghdad, have been severed repeatedly by insurgents who throw up impromptu checkpoints, summarily killing any Shiites they find. The killings had grown so frequent by last year that some local Shiites organized a vigilante force, but Sistani's aides quickly forced them to disband.

At times the insurgents have practically cut off Baghdad's Shiite majority from the holy cities of Najaf and Karbala and the Shiite heartland to the south. Some Shiites are convinced that Sunni extremists are trying to drive them out of a whole arc of small towns around the capital's rim. "This is ethnic cleansing," said Maliky. "They are surrounding Baghdad, and they want to eliminate the Shia. Madaen is the leadership point for them."

Hashimi's grisly CD-ROM seemed only to confirm those dire suspicions. Shiite politicians in Baghdad seized on the evidence to demand a crackdown on the extremists. Even so, the calls were for tougher police action, not vigilante moves. "Thank God almighty the place has stayed quiet," Yawer says. "There are some politicians who are trying to stir it up, and if they did, it would be like a fire on dry hay. I really must raise my hat to Sistani and the Shia marjiya [senior religious leaders] telling people to calm down."

Iraq's Shiites have centuries of practice at swallowing their anger. They have been a subject people for most of the past millennium, even though Shiism was born in Iraq. Many Sunnis seem utterly convinced that they were born to rule. Mishan al Jibouri is one of the few Sunni politicians who ignored the boycott calls and won a National Assembly seat. He insists on referring to Baghdad's Shiite majority as "guests" and makes it clear that he regards them as unwelcome ones. "Sunni Arabs were the ones who built Baghdad," he says, "and ever since the Abbassid Dynasty they have been ruling it." He insists that the Americans are plotting to hand the place over to Tehran.

Many of Iraq's Sunnis share that suspicion. "Every day we are approaching the moment of explosion," Jibouri warns. "Since Saddam fell, I've never been as concerned about the possibility of civil war as I am today." The risk of a breakdown is undeniable. But the ayatollahs seem determined to keep it from happening. Iraq's Shiites have kept their patience for 1,000 years and more. For the sake of assuming power at last, they may succeed in holding out a little longer.