The future of Syria and Iraq will be shaped significantly by the outcome of the battle of Mosul that is now underway.

The campaign launched earlier this week to liberate the northern Iraqi city of Mosul from ISIL control, immediately following the liberation of Dabiq in Syria, is likely to mark a historic turning point in the fate of ISIL in Syria-Iraq. It may also reveal prospects for the future political configuration of both countries.

Yet the actual consequences of this week’s events depend heavily on several critical military, demographic, and political developments whose outcome now is totally unknown.

These include: How fierce a fight will ISIL put up in Mosul, after not resisting much at Dabiq? Will Iraqi Sunni, Shia and Kurdish forces and political leaders be able to reach understandings on how to govern Mosul and other liberated areas? Will Turkey be satisfied that it has achieved its military-strategic aims in Syria and Iraq, and refrain from confrontations with Iraqi or Kurdish troops?

Historic moment of reckoning

It is already clear, however, that this is a historic moment of reckoning for almost every major actor involved in the battle against ISIL in northern Syria and Iraq.

This is owing to several major developments, including, most notably: ISIL’s steady loss of territory it controls; enhanced military coordination among fighting forces from half a dozen countries or parties; an apparent important step forward in internal Iraqi political understandings on how to defeat ISIL; and clarifications in the war aims of neighbouring powerhouse Turkey.

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The most important common of these and other factors is that ISIL’s military weaknesses are being quickly exposed as forces from many Arab and foreign quarters coordinate to attack important ISIL political bases, strategic logistical posts, and population centres.

Peshmerga forces take part in an operation to liberate several villages from ISIL control, southeast of Mosul, Iraq [EPA]

The battle to liberate Mosul has required serious, if often indirect, coordination and political understandings among the Iraqi government, armed forces, the police, the Kurdish forces in the north, Sunni tribal forces, Iraqi Shia militias that are close to Iran, the United States air force and special forces, along with other quarters that provide intelligence and logistic support.

Such coordination among the different military and political partners has been very slow to materialise owing to major political and territorial disputes among most of these parties.

The most important common consequence of these and other factors is that ISIL's military weaknesses are being quickly exposed...

It seems that the main parties in the Mosul battle have agreed on the limits of Turkish involvement and advances on the ground, and also limits on Iraqi Shiite militia involvement in the Sunni-majority city.

These new realities allow both Turkish and Iranian-influenced Shia-Iraqi forces to lend their weight to the battle without triggering fierce opposition from Sunni or Kurdish quarters that oppose them both.

In close coordination

Also significant in the campaign against Mosul has been the Iraqi armed forces and government taking the lead on the ground, and – unprecedentedly – fighting in close coordination with Kurdish forces.

This implies a critical new level of shared political appreciation that only these two groups of fighters should liberate the city on the ground, while others provide support from the air or in other ways, including intelligence and logistics.

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It also indicates that the Iraqi state armed forces have reached a level of technical proficiency and political self-confidence – both in their and others’ eyes – that they can undertake and even lead this move. Their full prowess will be tested in the battle to liberate Mosul.

A more capable and credible Iraqi army may augur well for the future state rebuilding prospects of the country, especially if it also reflects improved capabilities of the Iraqi police which actually handle security in cities and towns.

One imminent test will be whether the police have been able to train an expected 20,000 Sunni tribal forces to handle policing action in and around Mosul.

More capable, respected, and legitimate armed forces and police are needed to pull the country out of the cycle of regression and stagnation that it has had for the past decade, and allow the government and leading sectarian and ethnic forces to reach stable power-sharing agreements, reduce rampant corruption levels, and promote sustained development activities that improve the lives of ordinary Iraqis, including in realms such as electricity, jobs, incomes, and security.

FSA fighters cheer and react as they fight against ISIL on the outskirts of the northern Syrian town of Dabiq [Getty]

Turkey’s involvement

The direct military involvement of Turkey in both Syria and Iraq in recent weeks is a major new development that has helped to hasten the demise of ISIL in both countries.

The disruption of ISIL supply routes in northern Syria and the fall of the religiously symbolic town of Dabiq (where ISIL believes the apocalyptic battle at the end of days will occur) have exposed ISIL’s limited defence capabilities there.

The Mosul battle will show if ISIL also has limited will to fight when all its foes finally get together and attack it as a single coordinated force.

Turkey says it has achieved its key strategic objectives in northern Syria (to prevent a contiguous land area run by Syrian Kurds and drive back ISIL from near its border). We may find out in coming weeks if the US and Turkey join with local rebels in Syria to launch a combined attack on ISIL’s second most important base, the city of Raqqa in northeast Syria.

This and many other aspects of the future of Syria and Iraq will be shaped significantly by the outcome of the battle of Mosul that is now underway.

Rami G Khouri is a senior public policy fellow at the Issam Fares Institute at the American University of Beirut and a non-resident senior fellow at Harvard University Kennedy School.

The views expressed in this article are the author’s own and do not necessarily reflect Al Jazeera’s editorial policy.