The Middle East has spun so far out of control that US plans for a Palestinian state may be engulfed in a "clash of civilisations", writes Lara Marlowe.
Westerners have been intervening in the Middle East since the Crusades, invariably with disastrous consequences. The CIA-MI6 coup which brought the Shah of Iran to power, US support for the Israeli invasion of Lebanon, the funding and training of the mujahedeen in Afghanistan are but a few examples.
The Crusaders, at least, were honest about their objectives. In the last 200 years, such bald aggression became unfashionable. When they invaded Egypt, Algeria and Iraq in the 19th and early 20th centuries, France and Britain cloaked their interventions in the rhetoric of liberation.
In March 1917, Lieut-Gen Sir Stanley Maude ordered a proclamation posted on the walls of Baghdad. "Our armies do not come into your cities and lands as conquerors or enemies, but as liberators . . ," it said.
US Defence Secretary Donald Rumsfeld made a similar speech on April 29th, 2003: "Unlike many armies in the world, you came not to conquer, not to occupy, but to liberate, and the Iraqi people know this," he said.
But 2004 put paid to US and British claims about "liberating" Iraq. In the spring, the world was shocked by images of Iraqi prisoners piled naked in pyramids, threatened by dogs and attached to electrodes at Abu Ghraib prison. As the year drew to a close, the American Civil Liberties Union disclosed evidence that torture continued in Iraq after the scandal.
In October, a report published by the British medical journal The Lancet estimated that 100,000 Iraqis had died as a result of the US-led invasion. More than 1,200 US servicemen have been killed and six countries have pulled out of President Bush's coalition of the willing. Also in October, the Iraq Survey Group definitively refuted the main pretext for the invasion. Saddam Hussein had no Weapons of Mass Destruction; the inspections that Washington scoffed at were working.
To explain the violence in Iraq, Americans concluded that Iraqis were ungrateful. I first heard it from Sgt Sean Fox, a tank commander with the 1st Armoured Division, in April.
We stood beside a tank Fox had named "Blitzkrieg", after the Nazi military strategy. "My impression of Iraqis is that they're ungrateful," he said. "They're biting the hand that feeds them. They smile at you, and they shoot you in the back. I don't trust one of them."
At the Walter Reed Army Hospital in September, I heard similar words from Virginia Sanchez, whose son, Michael, lost his leg in Iraq. The Iraqis were ingrates, she told me.
The Shia slums of Sadr City, home to two-fifths of Baghdad's five million people, were the only district that welcomed US troops as liberators on April 9th, 2003.
Yet it was Sadr City that rebelled last April. The dusty streets were transformed into a battle zone. US M1 Abrams tanks and Bradley fighting vehicles hunkered down at intersections, their guns pointed at the populace.
Apache helicopters rocketed vehicles and houses. A car carrying an Iraqi family was crushed flat with the family inside it. It had taken only a year for the US military to begin killing the people they meant to liberate.
The Shia revolt started after the bombings of mosques in Karbala and Baghdad killed 170 worshippers on March 2nd.
Sheikh Moqtada al-Sadr's newspaper, al-Hawza Nataqa, accused US occupation forces of setting off the bombs, so the US administrator, Paul Bremer, shut the newspaper down. Explaining the Shia uprising to me, a hospital administrator in Sadr City said: "Iraqi people are not monsters. But there is a foreign object in their body, and they want to eject it." Sadr City teems with young men, most of whom claim to belong to al-Sadr's Mehdi Army militia. One of them, a 21-year-old named Haidar, told me: "We are all in Mehdi's Army. People are not frightened, because we are fighting for our religion. If they kill us, we'll be martyrs."
Just as George Bush portrays the Iraq war as one between good and evil, the clergy who lead the Iraqi insurrection cast it as a war between infidel invaders and Muslims.
Grand Ayatollah Ali Sistani, the highest religious authority among Iraqi Shia, finally managed to broker a truce between Moqtada al-Sadr and the Americans in August, saving the Shia shrine of Imam Ali in Najaf.
The Americans had sworn they would take al-Sadr "dead or alive", but that is forgotten now. There are contradictory statements about whether al-Sadr's faction will participate in elections for a national assembly on January 30th. If the elections are cancelled or postponed, al-Sadr's men would doubtless take up arms against the Americans again.
US forces cannot satisfy both the Shia majority, who demand elections that will ensure they rule the future Iraq, and the Sunni, who are fighting to prevent those elections taking place.
At the moment, the insurgency in Iraq is almost entirely Sunni, and it has united Saddam's former intelligence and military officers with fundamentalist Muslims.
The Sunni Association of Scholars acted as intermediaries in the fighting in Falluja and in the liberation of some foreign hostages. US troops have arrested dozens of clerics, whom they see as accomplices of the insurgents.
In Falluja, Sheikh Abdallah Jenabi headed the Council of the Mujahedeen that turned the city into an Islamic mini-state until US troops seized it in mid-November.
The Americans offered rewards for Sheikh Jenabi and Abu Mussab al-Zarqawi, the Jordanian extremist believed responsible for much of the bombing and hostage-taking in Iraq. But, like most of the fighters, both leaders escaped last month's onslaught against Falluja. Jenabi's council probably continues to function elsewhere.
In Falluja, the council forbade the selling of music, video-cassettes and alcohol. Offenders were flogged, while anyone suspected of collaborating with the Americans was killed.
Embedded journalists who entered Falluja with the Marines found posters bearing the council's symbol of two Kalashnikovs in a triangle, ordering women to veil themselves from head to toe. The penalty for disobedience was execution.
By adopting the most extreme Salafist rhetoric and methods, the insurgents frighten foreigners who might be tempted to participate in the reconstruction of Iraq. And they are more likely to win support from the loose network of jihadists around the world. (Salafists and Wahabis are Sunnis who want to live as Muslims did at the time of the Prophet. Their movement began in Saudi Arabia in the 19th century).
The insurgency against the Americans masks another conflict between Shia and Sunni. After 30 years of terrible repression by Saddam's Sunni-dominated government, perhaps it was inevitable that Shia and Sunni would clash once the lid of dictatorship was lifted.
The Sunni-Shia conflict in Iraq has enormous repercussions for the rest of the region. Saudi Arabia and Kuwait have large Shia minorities, so both are anxious at the prospect of the Shia ruling Iraq. Bahrain, home to the main US naval base in the Gulf, has a Shia majority ruled by a Sunni minority - like Iraq before the invasion.
By favouring the Shia and Kurds, US forces have increased religious and ethnic tensions. Most of those joining the Iraqi police force and army are Shia and Kurds; this is one reason the security forces are attacked so often.
In October, insurgents massacred 49 Shia army cadets. They were on their way south on home leave and were unarmed and unprotected. Shia Muslim travellers are often ambushed in the so-called triangle of death, where most foreign hostages were kidnapped, on the main highway south of Baghdad.
This autumn, a funeral cortège travelling from Baghdad to Najaf was stopped on the highway. The Shia mourners were gunned down by the roadside. In June, six Shia truck drivers from north Baghdad were kidnapped, tortured and murdered in Falluja after they delivered supplies to an Iraqi army base there.
When their relatives tried to find the truck drivers, Sheikh Jenabi told them: "Your sons are spies." One truck driver had a tattoo of Imam Ali, the founder of Shia Islam, on his arm. His Sunni torturers cut it out with a knife.
Another driver was shot in the mouth and scalped. All of the corpses were blindfolded, with hands and feet bound and fingernails torn out. One driver's back was burned with a toaster-like device. Several of the bodies appeared to have been dragged behind cars.
Ask any Iraqi if his country is on the verge of civil war and he will tell you that such talk is used by the Americans as an excuse to stay in Iraq, that there is too much inter-marriage between Sunni and Shia, that the Arab tribes upon which Iraqis base their identity are mixed. But, with every incident like the murder of the Shia truck drivers, one hears fewer protestations that Iraqis would never fight each other.
Meanwhile, the Kurds are ethnically cleansing the Arabs whom Saddam Hussein transferred to Kurdistan in the 1970s. The Kurdish leader, Jalal Talabani, says all Arabs will have to leave Kirkuk before elections can be held there.
Shia leaders in Basra have formed a new militia called the "Anger Brigades". Its purpose is to kill extremist Sunnis. Dhia al-Mahdi, the leader of the Anger Brigades, said in a written statement this month: "The Wahabis and Salafists have come together to harm fellow Muslims and have begun killing anyone affiliated with the Shia sect. The Anger Brigades will be dispatched to those areas where these germs are, and there will be battles."
Amid the violent chaos of post-invasion Iraq, a debate is starting similar to that around Algeria in the mid-1990s: who is killing whom? And why?
In July, the Sydney Morning Herald newspaper quoted two witnesses who said they saw Iyad Allawi, the interim prime minister, personally shoot dead six blindfolded, hand-cuffed suspected insurgents in the Al-Amariya detention centre "to show the police how to treat insurgents". Allawi has denied the accusation.
As happened in Algeria, the insurgents are believed to have infiltrated the US-backed security forces, and vice versa. It is a nightmare situation where no one can be trusted.
US and British diplomats travel the short distance from the Green Zone to Baghdad airport by helicopter. The airport road is too dangerous, the site of daily bombings and assassinations. Transport aircraft ferry 450 tonnes of supplies to US bases every day because road convoys suffer too many casualties.
President Bush's "Greater Middle East initiative" was supposed to transform Iraq into a platform to spread democracy throughout the Arab world. But the bloodbath in Iraq is not the only impediment to Mr Bush's plans.
"The US is seen as the imperial power in the region," says Dr David Ryan, of the history department of University College Cork, who is writing his second book on US interventions. "Resentment against the US is too extreme for people to accept any kind of American model or American-backed regime."
What can be done? The Europeans never cease telling Mr Bush that an equitable solution to the Israeli-Palestinian conflict would deprive Islamic extremists of their most effective recruitment advertisement. Yet Washington did nothing to prevent the Israelis destroying thousands of Palestinian homes over the past four years, or the deaths of some 4,500 Palestinians and Israelis.
Under Mr Bush's presidency, the Middle East has spun so far out of control that even the creation of a viable Palestinian state might be too late to stop the clash of civilisations. Hindsight is always better. It is easy to see now that the West should not have fuelled the Middle East arms race; should not have equipped and trained torturers; and should have encouraged freedom of speech so that mosques did not become the only forum for expression.
CIA reports obtained by the New York Times in July and December painted a sombre picture of Iraq's future. The insurgents seem to have an endless supply of suicide-bombers; more than 300 have already died, taking thousands of Iraqis with them.
The death by shooting or beheading of 37 foreign hostages in Iraq this year has come to symbolise the chaos there. Who can forget the wrenching images of Kenneth Bigley and Margaret Hassan? Can there really be hope for Iraq? Or did George Bush find a WMD after all? What if Iraq itself was the biggest Weapon of Mass Destruction?