The battle for Iraq’s second city, Mosul, is entering its final phase, signalling a significant shift in the status of politics in the Middle East. The eventual, if still lengthy and bloody, capture of the city will mark the Iraqi Army’s most significant victory since its post-Saddam Hussein inception, as well as a more clear delineation of regional ethno-political geography.

The most important marker of the impending Mosul victory will not be the defeat of the Islamic State in one of its key strongholds, but that this victory will be owned by the Iraqis. The Iraqi army has, in this, benefited from the assistance of Iranian “volunteers” and has been bolstered by Iraqi Shia militias as well as Kurdish Peshmerga forces to the north.

However, the US and its allies have played a minor role in the battle, mostly by way of providing air support and “technical assistance” on the ground. This is not, as so many of the earlier battles in Iraq had been, a predominantly US affair.

This low level of US and allied involvement will allow the Iraqi government a sense of ownership of the battle’s outcome. If Iraq is to avoid existing on the edge of state failure, it must increasingly take responsibility for its own circumstances, even if those circumstances are determined by others.

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The residents of eastern Mosul, recently liberated from IS control, have celebrated, even if they are overwhelmingly Sunni Muslims and their saviours are predominantly Shia. Indeed, some Shia exuberance at the victory being a sectarian one has had to be quelled, for fear of sparking a longer term backlash. It was this Shia-Sunni divide, and the withdrawal of a strong US presence, that led to the rise of IS in the first place.

Part of the longer-term resolution of IS’ temporary control of Mosul and other areas of Iraq will be the state’s reconsolidation, with its Shia majority having to make a conscious decision to actively include its Sunni minority. The third ethnic component of the Iraqi state, the Kurds, will present a different conundrum.

Kurdish forces have proven themselves time and again as formidable against IS and other jihadi groups in both Iraq and neighbouring Syria. They have also paid, and continue to pay, a heavy price for their anti-IS contribution.

The Kurdish leadership has been public about its desire to establish an independent state, which is again being discussed as quid pro quo for the Mosul liberation. Such a separation would diminish the state physically and economically.

Much if Iraq’s oil is in Kurdish territory, which is why what might otherwise have been an independent Kurdistan was carved up by the colonial British and French in 1916. This carve up — the Sykes-Picot Agreement — effectively created the arbitrary states that comprise the contemporary Middle-East, and which remains an underlying factor in the wars in both Iraq and Syria.

States, including Iraq, very rarely accede to voluntary diminution. At least as importantly, the Syrian regime would be loath to allow its Kurdish region to join such an independent Kurdish state (as would Iran, which also has a smaller adjoining Kurdish region).

[Turkey, the sick man of Europe once more]

The big problem, however, is Turkey, which is directly opposed to the establishment of a Kurdish state on the grounds that it would provide a base for its own Kurdish separatist movement. The creation of a Kurdish state would also place the US in an invidious position, with the Kurds to date having been the US’ most reliable local allies, but with NATO member Turkey opposing such a creation — possibly militarily.

The Iraqi government, also a US ally, has not yet responded to the proposal. However, given that the Kurdish region north of Iraq is already independent in all but name, the Iraqi government might have little choice in the matter.

Iraq might also find that a friendly independent Kurdish state is a good neighbour to a still fragile Shia-Sunni Iraq. At least, it would be much better than an unfriendly neighbour with a growing military record for protecting its turf.

*Damien Kingsbury is a professor of international politics at Deakin University