It was supposed to have been the day when Iraq's Shia Muslims celebrated their main religious festival in the freedom of a post-Saddam Iraq. It ended in carnage. Graham Usher reports from Karbala At first it was a dull thud and a blank look of fear on people's faces. Then another. Then came a third. Then a wall of flame so high it licked the tiles of four-storey hotels. People -- hundreds of them -- ran in panic. Some crouched behind market stalls. Some fled to mosques. In one surreal image two pilgrims, freshly bloodied from the tutbir ritual in which devout Shia Muslims lacerate themselves with swords, stood amid a fresher pool of blood and flesh next to a wrecked ceremonial coach. It was not the only moment in Karbala on Tuesday when the present of the majority Shia Muslim community in Iraq seemed to fuse irredeemably with its history. Four suicide and mortar bombs hit Karbala, leaving over 100 dead and 200 wounded, many of them Iranians. The bomber detonated on a busy market street; two of the mortars struck people milling near the Hussein and Abbas mosques; the last mortar cratered a main rod ferrying pilgrims. With Najaf, Karbala is the Shias holiest city in Iraq. Ashura is their holiest holiday. There could be no worse event, no greater sacrilege, said Hussein Shahristani, a Shia analyst in Karbala. "Shia pilgrims from all over the world came to Karbala to celebrate a religious occasion. After so many years of persecution the very least we expected in the new Iraq was to worship in peace. Yet we were exposed to these attacks." Tuesday was supposed to mark the climax of Ashura, 10 days in which Shias everywhere re-enact the martyrdom of Imam Hussein, the grandson of Prophet Mohamed. For the last 36 years in Iraq it represented a muzzled assertion of Shia identity and resistance against the might of Saddam Hussein's Ba'athist regime and the violence it inflicted on them. This year Saddam's army was replaced by Polish soldiers on the outskirts of Karbala and militias from the Shias main religious parties in and around its shrines. "It feels like an act of God's mercy," said one woman on Monday. It did not last long. Nor was the violence unexpected. There was a kind of terrible certainty about it. Most people in Karbala blamed Al-Qa'eda or its Iraqi surrogates, sowing inter-communal mayhem in Iraq to turn Shia against Sunni, Kurd against Arab. One month ago to the day twin suicide attacks slaughtered 100 in the Kurdish city of Irbil in northern Iraq. Many Shias feared their turn would be next. For a moment it appeared the sting might release its poison. In the immediate aftermath outraged Shias assaulted "outsiders", including foreign journalists. One Iranian pilgrim -- wounded apparently from the blast -- was abducted from an ambulance by a mob convinced he was somehow in league with the bombers. Iraqi police and religious militiamen rescued him, at the point of sword and machine gun. But then the rage subsided, calmed by Iraq's other confessional and national leaders, including those on the Iraqi Governing Council (IGC). They condemned the carnage in Karbala and elsewhere not as an attack by Sunnis on Shias but as attack on "Islam, Iraq and Iraqi unity". Karbala's religious leaders called for blood for the victims and discipline on the street. Most importantly, the Ashura ceremonies resumed, led by black-suited youths running through the streets and leading the people back to the mosques. At nightfall a final procession wended its way through Karbala's unlit streets, against a cry of lamentation and the monotonous beat of a drum. "This is how we will respond to evil and the dark forces ranged against us -- not with arms and weapons but with peaceful protests and demonstrations," said Abu Jafer Assadi, a security official at Karbala's main shrines. "Our belief in Imam Hussein is like a nail. The more you hit it the stronger it holds." Maybe -- but there is a political ransom to be paid for the Shias restraint. For now it is not being levied on their Sunni and Kurdish compatriots, whatever the aims of Al- Qa'eda or its like. If anything, the wholly indiscriminate violence now stalking Iraq is bringing its people together. Frustration rather is being voiced against the Americans and the occupation -- as opposed to the communities they protect. On Tuesday Karbala's religious leadership held the Coalition Provisional Authority (CPA) indirectly responsible for the attacks. There was particular anger that the mortars were fired from outside the city, where occupation soldiers were responsible for security. It follows anger over the CPA dismissal of the city's governor, allegedly for his overly close links to the clergy, but actually -- say locals -- over his demand that Karbala must decide who will police its shrines and that these should be drawn from the local religious party militias rather than "policemen" from outside. Above all the Shias discontent is over the US desire to delay elections to an Iraqi national government while enabling an appointed secretariat to make fundamental decisions about the future of their country. These were the main political slogans of this year's Ashura, even before the bombings. The Americans would do well to heed them, says Shahristani. "People do have a greater sense of religious freedom but there is a growing concern over not being allowed to elect the leaders they trust. Shias see the US dragging their feet on elections and Fundamental Laws passed by un-elected bodies. For now people have not taken things into their own hands. The religious leadership has been very careful about steering all protests away from any form of violence. But the world should hear what the Shias on the streets of Karbala are demanding -- the right to participate as equal citizens in a country in which they form the majority." This at least is the hope, and not only among the Shia religious leaders who have urged their people to struggle for democracy rather than vengeance. But if the nail's strength does not hold -- if some among Iraq's Shias decide not to "forgive their murderers" (as counselled by Assadi) but fight fire with fire -- then the future of Iraq is civil war and the Shia present will continue to endlessly repeat its past. "The Shia have a saying," said Lath Abdul-Lami, a pilgrim in Karbala from a village outside Baghdad. "We say every day is Ashura and every place is Karbala."