Before it became too dangerous for a foreigner to linger in the streets of Baghdad, I had often watched crowds dancing with delight among the burning remains of a US Humvee blown apart by a roadside bomb. It was by exploiting the solidarity of the five-million-strong Sunni community in the face of the occupation that the anti-Shia suicide bombers were able to carry out their murderous work with impunity and bring Iraq to the brink of all-out civil war.
Sectarian hatred was escalating rapidly. Until a few months before the bomb in Samarra, Iraqi friends used to say to me that Iraq was not like Lebanon. Now they were silent, or asked what the Lebanese civil war had been like. Districts where Sunni and Shia had lived together peacefully for decades, if not centuries, were torn apart in a few days.
In the al-Amel neighbourhood in west Baghdad, mixed but with a Shia majority, Sunni householders found envelopes pushed under their doors with a Kalashnikov bullet inside and a letter telling them to leave immediately or be killed. The reaction to the letter was immediate. The Sunni in al-Amel started barricading their streets. Several Shia families, believed to belong to the Supreme Council for Islamic Revolution in Iraq, were murdered the same day that the letters were received. "The local Sunni suspected those Shia of being behind the letters," said my informant. "Probably they called in the local resistance and asked them to kill the SCIRI people."
Day-to-day survival in Baghdad meant taking life-or-death decisions for mundane reasons. By the end of March it was beginning to get hot in the city, and people normally at this time of year buy summer clothes. Many shops were closed because the owners were too frightened to leave their homes. But staying in your own house also brought problems with it.
In the torrid summer heat, people need air conditioning to make life tolerable. But Baghdad was getting only three or four hours of electricity a day. Almost everybody had a generator, large or small, and the price of petrol was heavily subsidised by the state. One friend, Muhammad, complained: "Either I wait seven or eight hours in a queue to buy fuel or I get it on the black market. But that means I could have to spend $7-$8 a day to run my generator and I simply can't afford that."
"The battle for Baghdad has already started," said Fuad Hussein, the chief of staff of the Kurdish leader, Massoud Barzani. "The fighting will stop only when a new balance of power has emerged. Sunni and Shia will each take control of their own areas." He pointed to such districts as al-Dohra and al-Ghazaliyah, where the insurgents or the Sunni political parties were tightening their grip. In the first half of 2006 Iraqi political leaders were increasingly pessimistic about Iraq holding together as more than a loose confederation. "The army will disintegrate in the first moments of the war, because the soldiers are loyal to the Shia, Sunni or Kurdish communities," one senior official said.
A few weeks later, at the end of April, there were ominous signs that these predictions of street fighting were beginning to come true. Adhamiyah is one of the few solidly Sunni areas in Baghdad. Its people regarded the police and paramilitary commandos as little different from death squads. Over several days in the middle of April, Adhamiyah resounded to the sound of gunfire and exploding rocket-propelled grenades. American and Iraqi soldiers claimed insurgents had tried to ambush them. Local people said that, on the contrary, the young men of the district had fought off an invasion of their streets by Shias bent on killing and kidnapping. Sunni gunmen raced from house to house calling for each family to send at least one of their sons to join the battle.
After three years in Iraq I thought I had become all too inured to violence. I no longer responded to bloodshed, except with the usual words of regret, unless people I knew well were killed and injured. But in Iraq, just as I was imagining I had seen the nadir of savagery, I would hear of something worse.
This is an edited extract from 'The Occupation: War and Resistance in Iraq' by Patrick Cockburn (Verso, £14.99). To buy a copy for £13.55 with free p&p, call Independent Books Direct on 08700 798 897 or go to www.independentbooksdirect.co.uk