What are they fighting about in Basra?

The wars in Iraq (the plural is no typo) are about to expand and possibly explode, so it might be useful to have some notion of what we're in for.

Here is President George W. Bush, speaking this morning in Dayton, Ohio, and revealing once again that he has no notion:

[A]s we speak, Iraqi security forces are waging a tough battle against militia fighters and criminals in Basra—many of whom have received arms and training and funding from Iran. … This offensive builds on the security gains of the surge and demonstrates to the Iraqi people that their government is committed to protecting them. … [T]he enemy will try to fill the TV screens with violence. But the ultimate result will be this: Terrorists and extremists in Iraq will know they have no place in a free and democratic society.

The reality, alas, is less stark. The fighting in Basra, which has spread to parts of Baghdad, is not a clash between good and evil or between a legitimate government and an outlaw insurgency. Rather, as Anthony Cordesman, military analyst for the Washington-based Center for Strategic and International Studies, writes, it is "a power struggle" between rival "Shiite party mafias" for control of the oil-rich south and other Shiite sections of the country.

Both sides in this struggle are essentially militias. Both sides have ties to Iran. And as for protecting "the Iraqi people," the side backed by Prime Minister Nouri al-Maliki (and by U.S. air power) has, ironically, less support—at least in many Shiite areas, including Basra—than the side that he (and we) are attacking.

In other words, as with most things about Iraq, it's a more complex case than Bush makes it out to be.

The two Shiite parties—the Islamic Supreme Council of Iraq and Muqtada Sadr's Mahdi army—have been bitter rivals since the early days of post-Saddam Iraq. And Maliki, from the beginning of his rule, has had delicate relations with both.

Sadr, who may be Iraq's most popular Shiite militant and who controls several seats in parliament, gave Maliki the crucial backing he needed to become prime minister. However, largely under U.S. pressure, Maliki has since backed away from Sadr, who has always fiercely opposed the occupation and whose militiamen have killed many American soldiers (until last year, when he declared a cease-fire).

Maliki has since struck a close alliance with ISCI, which has its own militia, the Badr Organization, and whose members also hold much sway within Iraq's official security forces (though more with the police than with the national army). This alliance has the blessing of U.S. officials, even though ISCI—which was originally called the Supreme Council for the Islamic Revolution in Iraq—has much deeper ties with Iran than Sadr does. (ISCI's leaders went into exile in Iran during the decades of Saddam's reign, while Sadr and his family stayed in Iraq—one reason for his popular support. As Ray Takeyh of the Council on Foreign Relations has noted, SCIRI was created by Iran, and the Badr brigades were trained and supplied by Iran's Revolutionary Guard.)

Sadr's Mahdi army and ISCI's Badr Organization came to blows last August in the holy city of Karbala. This fighting—and his growing inability to control criminal elements within the Mahdi army—spurred Sadr to order a six-month moratorium on violence, which he renewed last month, against the wishes of some of his followers. (This moratorium is a major reason for the decline in casualties in Iraq, perhaps as significant as the U.S. troop surge and the Sunni Awakening.)