And now 4,000 allied deaths, at least 100,000 Iraqi deaths and somewhere around $1 trillion later, the question of whether the war was just or made sense remains uncertain. That uncertainty will last for a long time, because one of the main unspoken goals of the war is still developing.
There were three official goals of the war to topple Saddam Hussein, according to Paul Wolfowitz, then deputy defense secretary: "One is weapons of mass destruction, the second is support for terrorism, the third is the criminal treatment of the Iraqi people."
That argument looks feeble today. There were no weapons of mass destruction, though not for want of trying by the Iraqi regime. There were no serious links between al-Qaida and Saddam Hussein, and while he had offered sanctuary for some terrorist figures, the main supporter of terror in the region has been and remains Iran, which has been strengthened by the war.
Few would argue with Wolfowitz's point about the criminal treatment of the Iraqi people. Saddam was one of the world's most brutal leaders, and none should mourn his passing. But Iraqis have probably died in greater numbers since his fall than under his boot, and some 3 million of them, more than 10 percent of the population, have gone into exile.
The unspoken goals of the war were rather different. There were several. One was to reassert the dominant strategic role and presence, and the resolve of the United States in the oil-rich region. Another was to demonstrate to all potential enemies the punitive costs of opposing the United States and its high-tech military.
But the central unspoken goal of the war was to kick over the sandcastle, to transform a Middle Eastern status quo that had become unstable, unfriendly and hopeless.
Consider how the region looked in 2002 and early 2003, with the bombing campaign under way inside Israel and the Oslo peace process dead.
The Saudi monarchy was in desperate financial trouble, its budget in deficit and its national income overhead shrunk from around $20,000 in 1980 to $8,000 in 2002, and a homegrown terrorist opposition was building fast.
Lebanon was under effective Syrian rule, Libya was buying nuclear technology from Pakistan's A.Q. Khan, Iran was shipping weapons into Gaza and the West Bank, Egypt looked hideously instable, and the whole region seemed trapped in a state of existential despair.
In 2002 the U.N. Development Program caused a sensation when it commissioned some reform-minded Arab economists, social scientists and intellectuals to write reports on the region. The first report, which said bluntly that the Arab world suffered from a lack of freedom, education and women's rights, was downloaded (in its Arabic version) over a million times from the Internet.
The underlying message was that the Arab world was in danger of becoming a failed civilization: that Spain alone had a greater gross domestic product than the entire Arab League with 10 times Spain's population; and that Spain alone translated more books into Spanish every year than the Arab world had translated into Arabic over the past 1,000 years. Spain, as the Arab world's lost colony, was a particularly pointed comparison.
The second report in 2003 analyzed the "knowledge deficit" more deeply and looked at the high illiteracy rates, the failures in Arab education and the role of Islam in fostering a culture of learning by rote and submission to authority and tradition rather than to creative and independent thinking.
One important symbol of the changes that were stirring in the Arab world, the independent al-Jazeera TV network, commented of the 2004 report: "True democracy is absent and desperately needed. Most of the time human rights are no more than a poster hung in sham councils and organizations. The educational system is severely retarded; schools produce ignorant young men and women who excel in rote memorization more than educated innovators. Most intellectuals, even if they deny it, realize that most of what was said in the most recent Arab Human Development Report is true."
The deepest purpose of the Iraq war was to break this pattern, to kick-start reform and political change, economic and cultural modernization and maybe even the first shoots of democracy in the Arab world. This concept, as defined in a series of striking speeches by President Bush and national security adviser Condoleezza Rice, was widely mocked, and the ambition of democracy may have been asking for too much too soon.
But to look at the Middle East today is to see a region transformed. The center of gravity is no longer the Levant, trapped in the obsession with Israel and the Palestinians, but the Gulf states, where oil is no longer the only source of wealth. Dubai as a trading port and tourist center, Qatar as a media and medical school center, Saudi Arabia with its new universities, are countries going through a cultural and intellectual revolution.
And watch the way the oil wealth is spreading, with massive investments in Egypt and Morocco and Tunisia, in Pakistan and India and China, and in vast new industries like the SABIC petrochemical giant.
Maybe the war did not provoke all this, though its effect on the price of oil certainly helped. Maybe it only accompanied a change that was already under way. Maybe the floundering of the U.S. military in the first four years after the invasion helped give America, democracy and reform a bad name. All that matters a lot less than the fact that much of the Arab world is surging out of its despair and medieval mindset.
Leave it to the historians to assess what part the war played in this. But to this reporter, it seems that the war was an essential catalyst to the way the Arab world is simultaneously undergoing its version of the Renaissance, the Reformation and the Enlightenment. And about time, too.