What lies ahead when ISIL is finally defeated?

Stephen Blackwell looks at the possible consequences of a collapse of ISIL in Iraq and Syria

The steady erosion of ISIL’s hold on its core territories in Iraq and Syria appears to herald the final success of the US-led coalition’s effort to overthrow the self-proclaimed caliphate.

As the attack onMosul intensifies and Syrian regime forces and Kurdish fighters close in on Raqqa, ISIL is mounting a desperate defence of the shrinking area over which it still holds sway. However, it is probably far too early to write off a regional threat that can still call on clandestine, international networks of followers to sustain its fanatical and uncompromising struggle against western countries and their regional allies.

Over the past year, the “caliphate” has lost a third of the territory it previously claimed jurisdiction over. In Iraq, a coalition of regular army and Shia militias has reconquered Fallujah, Tikrit and Ramadi and effectively liberated Anbar province. Kurdish forces operating in the north of Syria and a Turkish clampdown on smuggling routes have cut off key conduits that helped supply ISIL with new foreign recruits, weapons and money.

Eschewing direct offensives against Syrian and Iraqi forces, ISIL’s tactics have become increasingly defensive and based on insurgent hit-and-run attacks and scorched-earth measures. Crude oil production, a key source of finance for the extremists, has been steadily reduced by air strikes and the loss of territory. ISIL fighters have seen their salaries halved and the group has had to resort to criminal activities, such as bank robberies, extortion and illegal fund-raising, to make up a serious shortfall in revenue.

Despite this, much hard fighting will be necessary before Mosul and Raqqa finally fall. While the territory controlled by Abu Bakr Al Baghdadi and his followers continues to shrink, hundreds of lives have been taken in recent attacks across Turkey, Syria, Iraq and Afghanistan.

The work of reconstruction and rehabilitation of traumatised local populations formally under ISIL control will be immense. At the same time, any residual insurgency sustained by the remnants of the groups has ample scope to cause mischief given the absence of effective governance in large areas of Syria. The balance of political forces in Iraq remains brittle due to persistent sectarian rivalries.

United States secretary of defence Ash Carter acknowledged this during his recent visit to the Mosul front. Mr Carter called for the “stabilisation of Iraq and our continued willingness to lead a coalition in support of the consolidation of Iraqi government control over Iraqi territory”.

The US and its allies will undoubtedly be haunted by their failure to ensure strong central government in Iraq after the 2003 invasion, and the continued fragility of the regime in Afghanistan.

It appears inevitable that ISIL, deprived of its proto-state, will spread and deepen its underground international networks in order to plot a new wave of attacks on the West and its regional allies. Recent atrocities indicate that it will continue to export its blend of extremism and violence into the hearts of enemy countries.

Until now, the organisation’s quest to build a transnational network has proved to be its undoing. It has been stretched too thinly by attempts to set up mini-enclaves supposedly purified of foreign and apostate influences in remote areas from Libya to Afghanistan.

However, the loss of autonomous territory in Iraq and Syria could actually be to the group’s advantage in the future. What remains of ISIL will no longer be burdened with the administration and defence of defined areas in the face of a hostile international coalition, and it can instead channel its efforts into raising funds and planning and executing destructive attacks.

Freed from the need to hold territory, ISIL could redouble the propaganda effort that serves its universal mission of promoting an extreme puritan vision uncorrupted by the more limited local or regional agendas of other violent groups.

The dispersal of ISIL’s fighters could therefore provide a greater threat than its putative independent state. Recent attacks in Europe reveal the potential of just a few determined operatives to cause widespread disruption and sow fear and distrust among ethnically diverse societies. Small insurgent groups and lone operatives have launched attacks on “soft” targets, spectacularly and tragically in incidents such as the Brussels airport bombing. Intelligence agencies in Europe say that at least 1,000 ISIL adherents with military training and combat experience remain at large on the continent.

The pattern of attacks stretching from western Europe to Afghanistan suggests that the magnitude of the threat is likely to grow in the short to medium term. As the current military operations in Syria and Iraq wind down, international efforts to neutralise the diffused ISIL networks will increasingly depend on efficient intelligence and police work. The war against extremism will not be declared won in a conventional sense; the conflict will instead evolve into a new form of struggle that will only be overcome by vigilance, transnational cooperation and sustained efforts to discredit a murderous ­ideology.

Stephen Blackwell is an inter­national politics and security ­analyst