Analysis by the Royal United Institute (RUSI)
“To what extent will the current components which make up the UK terrorist threat change over the next three years?”
The terrorist threat to the UK comes from three types of threat actor. The most capable and determined are violent Islamists, principally Daesh, AQ, and their various franchises and affiliates, together with individuals or networks inspired by their ideology. Second are XRW groups and individuals, generally viewed as being less capable, but surprisingly numerous in counter-terrorism casework. The third set comprises a wide range of nationalist-separatist groups, the most significant being dissident republican groups in Northern Ireland. Other nationalist or separatist groups (such as Sikh extremists, Palestinian nationalists, Kurdish separatists) have been quiescent for many years.
Daesh is down but not out, and it will remain the greatest terrorist threat to the UK for some time to come.
It almost goes without saying that Daesh is the major threat to the UK and its interests and has been since it emerged in 2013. While celebrations of its imminent demise have been premature, it has undeniably lost most of its territory in Syria and Iraq under military pressure from the Global Coalition. This fact changes but does not eliminate the threat of Daesh-directed attacks against Western targets.
Territory is important as it has provided Daesh with resources as well as space in which to plan and operate. However, it is the loss of territory that may be the greatest determinant of intent to mount external attacks. After Daesh started to come under territorial and military pressure from 2014, its declared strategy changed to embrace attacks in the West in addition to state building and expansion within its Middle Eastern heartlands. As Daesh’s territory continued to shrink in 2015-17, the tempo and severity of Daesh-linked attacks in the West (and against Western interests) increased.
But Daesh-directed attacks in Europe have tailed off in 2018, so are we – as some analysts have asserted – over the worst? Not necessarily. In July 2018, Daesh South Asian franchise ISKP claimed one of the deadliest attacks in Pakistan’s history, which killed over 130 people in Baluchistan. Daesh affiliates are active in regions extending from West Africa to the Philippines. Moreover, there are reasons to be fearful about the threat in the longer term. Daesh is a product of many factors but governance failures and political and economic grievances are among the most important. These are getting worse, not better, in most of the countries that have fed Daesh recruitment, including Syria, Iraq, Libya, Sinai and Yemen. Then there are the thousands of Daesh recruits, including the so-called foreign terrorist fighters (FTFs), who remain unaccounted for.
Since 2013, over 40,000 men, women and children from 80 countries are estimated to have travelled to Iraq and Syria to connect with Daesh. Around 5000 are estimated to have come from Europe, and only 1500 of these are believed to have returned. 900 individuals of security concern are estimated to have travelled from the UK, of whom around 40% have returned, with 20% estimated killed, leaving around 360 presumably at large.
Fears of foreign fighters are not misplaced but they are probably exaggerated.
Since 2014, a major concern has been that these foreign fighters, radicalised and motivated, armed with battlefield skills and linked to new extremist networks, will return home and mount terrorist attacks. Empirical research suggests that a very small proportion of returnees go on to attempt terrorist attacks, and most of these take place in the first 12 months after return. Thomas Hegghammer estimated that up to one in nine returnees might become terrorists, but his more recent data-driven research with Peter Nesser suggests that, in the Daesh era, the figure is closer to one in 360.
Nevertheless, given the numbers who travelled in the first place, such figures may give little comfort, especially when the risk tolerance for terrorism is so low in the UK. And if Daesh planners are determined to use Western fighters to mount attacks in their home countries, as happened with the attacks in France and Belgium in 2015 masterminded by Abdelhamid Abaaoud, who had travelled to Syria in 2013, they have plenty of personnel to draw upon.
“Homegrown” terrorists, inspired but not necessarily directed by Daesh or AQ, will remain the biggest problem.
The low conversion rate from foreign fighters to domestic terrorists suggests that we should be more concerned about those who never went to Syria and Iraq. Indeed, experience suggests we should be at least as concerned about individuals who were prevented from travelling to conflict zones as those returning from them: Michael Adebolajo, one of the murderers of Fusilier Lee Rigby in 2013, was arrested in Kenya in 2010 and was believed to be travelling to join al Shabaab, an AQ-affiliated group, in Somalia.