I've been following a number of Iraqi blogs. One of which suggested this article as an explanation of what's going on there. It's very long, very informative and, seemingly, unbiased. I'm injecting just 4 paragraphs from it, but I encourage all to read it all. At least it gives one perspective that is deeper than the usual sound-bites given us by the media.
http://www.bostonreview.net/BR31.6/rosen.html In an attempt to limit Muqtada’s power and appease Sunnis, the Americans pressured Prime Minister Ibrahim al Jaafari to step down. He was replaced in May 2006 by Nuri al Maliki, his close friend, but American and British bullying cost them the few Shia allies they had and only convinced Iraq’s Shias that Americans were playing a game of divide and conquer. The debate over Jaafari was framed as Kurds and Sunnis competing with Shias for power. It was one more sectarian battle, fought this time inside the Green Zone. But it was too late for that game because the Americans had long since lost the Sunnis and were continuing to alienate them with daily killings and their protecting with force the Shia-dominated order that they created in April 2003. This American blunder has only pushed Iraq closer to Iran and Syria.
Nuri al Maliki is ideologically at least as extreme as Jaafari, and as committed to preserving the new order. He has already threatened to use “maximum force” against “terrorists,” the code word for Sunnis. Even if Maliki was committed to a national unity government and nonsectarian security forces, and even if the Americans tried to reverse the sectarian trend in Iraq, it is too late. Muqtada’s supporters will not voluntarily relinquish control of the army or the police, and having fought the Americans in the past, many would be eager to fight them again. And who would replace them? There are no nonsectarian Iraqis left, no nonsectarian militia, and no physical space for those rejecting sectarianism. Even secular Sunnis and Shias are embracing sectarian militias because nobody else will protect them. Many even join these groups out of fear, since to refuse is to be disloyal, or perhaps a spy.
Although the Bush administration has criticized the Iraqi government for not disarming the militias—and this is certainly the most important problem facing Iraq, apart from the occupation—this is an untenable first step. The militias exist because there is no security in Iraq. And when the Bush administration criticizes the Iraqi government for being weak, they forget that they deliberately made it weak and dependant on their dictates. The American failure to provide security has led to the militias. The American sectarian approach has created the civil war. We saw Iraqis as Sunnis, Shias, Kurds. We designed a governing council based on a sectarian quota system and ignored Iraqis (not exiled politicians but real Iraqis) who warned us against it. We decided that the Sunnis were the bad guys and the Shias were the good guys. These problems were not timeless. In many ways they are new, and we are responsible for them. The tens of thousands of cleansed Iraqis, the relatives of those killed by the death squads, the sectarian supporters and militias firmly ensconced in the government and its ministries, the Shia refusal to relinquish their long-awaited control over Iraq, the Kurdish commitment to secession, the Sunni harboring of Salafi jihadists—all militate against anything but full-scale civil war.