The Iraqi military’s attempt to retake Tikrit from Islamic State tells us several things about the current politics of the region. First, the Iraqi state is heavily reliant on the Iranians for military assistance. The Iranian Fars News Agency has reported that this assault is being backed by the Iranian Revolutionary Guard including the commander of its elite Quds Force, Maj. Gen. Qasem Soleimani. Reuters says that Soleimani can be seen directing operations from a hill and that his presence is crucial in terms of controlling the Iraqi Shi’ite militias, many of whom are Iranian trained.
Second, there is a danger that Islamic State might succeed in precipitating the sectarian war within Islam that it so desperately wants. Islamic State brutally murdered a thousand or more, largely Shi'ite, Iraqi soldiers in Tikrit last summer. As the New York Times reports, some of the Shi’ite militias groups are describing the current operation as a revenge mission. If this results in the slaughter of Sunni civilians, it will make the task of putting Iraq back together even more difficult—Islamic State’s rise was made easier by the deep suspicion that many Sunnis had of the previous, Shi’ite dominated government in Baghdad.