Nadhim Zahawi is a member of the BIS Select Committee, the Party’s Policy Board and MP for Stratford on Avon.

Iraq is unravelling. For the las ttwo weeks, the world has watched as borders, internal and external, have fundamentally shifted. The festering conflict in Syria has finally taken its toll and Iraq has descended into violence, upending the clearly delineated Sykes-Picot vision of the Middle East that has defined the region for a century.

As Syrian warplanes bomb militant positions, and battalions from the Iranian Revolutionary Guard take up positions in Baghdad and the holy Shia sites of Karbala and Najaf, we are in danger of letting the military narrative take over. One where the inevitable response to terrorist control of vast swathes of Iraq becomes large-scale military intervention.

For although the US government has proclaimed that limited military aid was based on a political plan of national unity, Nouri al-Malaki, Iraq’s Prime Minister has done little to heed these calls. In the end. a political solution is fundamental, and must be the focus if the gains made by ISIS are to be countered.

Since 2003 any kind of comprehensive political settlement in Iraq, or indeed any agreement on the nature of the post-2003 order, has been elusive. And it has been this failure to build a sustainable and inclusive political system that has allowed ISIS to thrive in the western deserts of Iraq, filling the vacuum of those who have been marginalized by the authoritarianism of the Malaki government.

Fatally in the early days of the Coalition’s Provisional Authority, rather than initiating any kind of meaningful process of reconciliation, Paul Bremmer took the short-sighted decision to disband the Iraqi army, and proceed with a deep and widespread process of de-Ba’athification. Hundreds of thousands of men, mainly Sunni, were sent home with no prospect of supporting their families. This has had a lasting legacy.

Tensions have been further compounded by Malaki’s divisive, sectarian policies; the central government has long lacked the inclusive approach vital to an emerging democracy, like South Africa. It has denied the political and financial decentralization demanded by both the Sunnis and the Kurds. And ISIS have finally used this to their advantage.

Despite the asymmetry in numbers, equipment and training, ISIS managed to rout the Iraqi Army within hours. And it is this speed which some have suggested exemplifies the how artificial the nation-state of Iraq is. The reality is more complex.

On a recent parliamentary delegation to Iraq, the Governor of Nineveh made it clear to us that ISIS had long had a presence in Mosul, first exploiting the legacy of invasion, and gradually expanding into towns and cities in northern Iraq by opportunistically manipulating disaffection with the central government.

Yet in reality most Sunnis do not identify with ISIS and the desire for a caliphate across the Levant. This is a revolt against Baghdad, rather than the mass uprising and formation of a fundamentalist Islamist insurgency. The deepening sectarian extremism is the product of a fundamentally dysfunctional political order.

Ten years after regime change we have a central government that in some respects looks very much like Saddam’s – with nepotism, mutual distrust and fear continuing to contaminate Iraqi politics. Rather than initiating any meaningful process of reconciliation, the Malaki government has exacerbated ancient strain and recent stresses, drawing even greater power inwards and denying the political and economic decentralization demanded by the Sunnis and the Kurds. This was not the kind of Iraq that they, or we, signed up for.

Iraq is at a cross-roads. We now occupy a ‘post-Mosul’ world, and there is no going back. It would be misguided to maintain loyalty to the failed post-2003 attempt at building a centralized federal state. It has merely allowed power to be hoovered up and left others feeling marginalised. What remains is an angry and alienated population and a violent Islamist insurgency.

But there is a danger of going too far the other way; the disintegration into three states will not deliver stability either. The promotion of partition based on the “artificiality” of Iraq fails to recognise that the three-way partition into ethno-sectarian entities equally lacks any kind of historical resonance, geographic clarity, or precedence in secessionist movements based on Sunni or Shia ideology. Artificial as it may be, Iraq has become a focus of robust national identity since the 1920s.

Indeed, is it not more false to impose the idea of the ethnically homogenous European nation-state on a region historically dominated by multi-ethnic empires?

I believe that greatest opportunity for Iraq lies in a third way, in a form of asymmetric federalism. This model would recognise the realities on the ground (although as I write, the situation is shifting minute by minute) and would better serve the interests of all parties. It is not a new concept, and has been used to recognise diversity and tensions in several other countries, including Banda Aceh in Indonesia, the Basque and Catalan regions of Spain, and more historically, our own,

Focus groups run by YouGov have shown that Sunni areas do not identify with an independent state in the same way as many Kurds do. But what they do want is a bigger share of the political pie in Iraq. Unfortunately, the federalism enshrined in the 2005 Iraqi constitution has yet to be given a fair chance; what we have seen over the past eleven years has only been a half-hearted attempt, pushed by the Kurds, and undermined by the central government.

Ultimately, neither centralisation or secession is preferable to the federal model – it is a way to keep Iraq together and help it become the country we want it to be. But changing how it is implemented could be the way to resolving this high stakes game.

The problem with the Iraqi constitution was that it initiated a symmetric “coming together” framework, whereby levels of autonomy should be equivalent for all regional governments. Yet it fundamentally failed to recognise the clear asymmetric foundation of the Kurdish safe haven of the 1990s, or recognise that it was unrealistic to expect the Kurds to retreat from the levels of self-governance they had achieve during the long and bloody Saddam years.

An asymmetric ‘holding together’ model would better promote stability by serving the interests of all. It most accurately reflects the country’s enduring ethnic and political realities, as well as those of the post-Mosul Iraq. And with their defence of Kirkuk, the Kurds have removed some of the fundamental barriers between themselves and the central government. Exclusive levels of autonomy would provide an acceptable solution while allaying fears of disintegration.

Some have suggested that such talk undermines the American effort to push the country to a more inclusive government, but on the contrary it actually offers the opportunity to put in place a more realistic system of governance.

But unless moves towards reconciliation are made, between Sunni and Shia, Arab and Kurd, the facts on the ground may make it too late to save Iraq. Calls for a government of National Unity have fallen on deaf ears; Malaki has argued that any such move would undermine the democratic elections held in April. But events have overtaken him.

It is now up to Iraqi politicians to overcome their differences and construct a national platform that addresses the countries challenges. Whoever is Prime Minister needs to have the credibility to bring the country together, with the confidence to allow for a democratic, pluralistic and decentralised Iraq.