It will be a high-level gamble for the Iraqi government to deploy its new multi-ethnic security force, the Golden Lions, in Kirkuk when the American forces withdraw. The dramatically named force will face a major challenge if ever the security situation in the city disintegrates. Kirkuk is the flashpoint for Iraq's future, where the simmering tension between the Sunnis and Shiite-backed Baghdad government will come up against the determination of the Kurds to manage their own autonomous territory in the north of Iraq.

The Kurds' desire to bring Kirkuk into their provinces is not just about controlling territory or numbers of people, but about controlling the valuable oil reserves buried below Kirkuk. A major factor for the future success of any Iraqi (or Kurdish) government is that it will control the huge oil revenues, and be able to spend the money so as to attract support from Iraq's many warring militias and ethnic and religious groups.

Kirkuk is ethnically split between Kurds and Arabs, and in the last general election the Kurds took about half the seats in the city. The vital Kurdish participation in the current ruling coalition in Baghdad means that the Kurds do not expect this government to take Kirkuk away from them, but organised Sunni Arab immigration into Kirkuk has boosted the Sunni Arab population, and reduced the Kurdish proportion.

The issue has been so sensitive that there has been no provincial election since 2005, when an Arab boycott gave the Kurds a disproportionately high number of seats. If the Kurdish provinces were normal parts of mainstream Iraq, the status of Kirkuk would not be so sensitive. But given the Kurds' autonomous status, violence in Kirkuk could be the issue that rips the present coalition apart.