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With Isis on the back foot in Mosul in Iraq and Raqqa in Syria, it is only a matter of time until the terrorist group loses its so-called caliphate.

While its appeal to foreign recruits was partly based on controlling territory, it would be naive to think that military defeat means the group is vanquished. In anticipation of the end game in Iraq and Syria, governments need to do all they can to eliminate Isis before version 2.0 mutates into something even more virulent — essentially a virtual caliphate.

In fact, that mutation is under way. In the nearly three years since Abu Bakr al-Baghdadi, the Isis leader, proclaimed the so-called caliphate in Mosul, the organisation has dedicated significant energy to attacks outside Iraq and Syria and hundreds of its victims have been killed in places far from the Middle East.

The attack in London last month was only the most recent: in Europe and North America, 330 civilians have been killed in more than 20 Isis-inspired or -directed attacks, and hundreds more injured. In Turkey, more than 300 civilians have been killed.

For some time, experts had been predicting that increased military pressure on Isis’s core in Iraq and Syria — driven by a handful of countries in the 68-member, US-led global coalition — would cause the terrorist group to lash out on the periphery, in order to demonstrate its staying power.

Such attacks ensure a flow of fresh recruits by promoting an image of the group’s invincibility: the international community is pounding Isis and yet it is still able to cause significant harm elsewhere. As the group loses its territorial grip, we can expect more attacks unless greater efforts are made to prevent them.

While significant gains have been made by the coalition, in partnership with local forces, not just in Iraq and Syria but also in Libya, overall it has not been able to halt the violent ideology as it metastasises across the world. The coalition was, in any case, designed to defeat Isis in Iraq and Syria, and not tackle out-of-area challenges.

In response to recent attacks, a number of countries have been reviewing and upgrading their domestic counterterrorism capacities to deal with recent attacks, often learning from experiences elsewhere.

Donald Trump, the US president, promised a plan to defeat Isis. No such plan was released at the coalition meeting in Washington last month, while it appears the short-term strategy of James Mattis, US defence secretary, is to increase troop numbers in Syria and Iraq.

That will accelerate the defeat of Isis in these two countries, but will not stop attacks elsewhere. For that, more proactive global leadership is needed — whether led by the US, the coalition or some smaller association of countries, such as the UK, with expertise in integrating counterterrorism capabilities.

The good news is that the strength of Isis globally is not as significant as the group would like to portray, either through directing and inspiring external attacks or through its network of affiliates, which include Boko Haram in Nigeria as well as groups in Southeast Asia, north Africa and elsewhere.

Isis 2.0 may well evolve into a loose affiliation of groups, with pockets of territory in a few weak states, and a virtual leadership that controls adherents through social media and encrypted technologies. Isis is not yet capable of carrying out a synchronised, global attack involving both core and affiliate groups. It should never be allowed to develop that competence.

President Trump’s pledge to “eradicate this evil from the face of the earth” is unlikely to be realised. Ideologies are difficult to defeat, especially under the current coalition strategy, which is not focused enough on stopping out-of-area attacks and disrupting Isis 2.0. A more concerted, cross-border strategy could reduce the threat posed by Isis and its likely successor. Given the scale of global attacks and the potential for more, it is time to be more ambitious.

The writer is director-general of the Royal United Services Institute, a defence and security think-tank

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