March 9, 2016

TSG IntelBrief: Foreign Fighters and Those Who Return

• The number of foreign fighters with the Islamic State has increased, but so too has the number of returnees

• Although foreign fighters make up for a lack of local recruits, the Islamic State appears to be getting weaker, at least in Iraq and Syria

• The Islamic State’s relatively weakened position in its primary territories of control may prompt an increase in attacks elsewhere

• Not all returnees are domestic terrorists in waiting, but it is hard to know which ones could be.


Recent suggestions by the United States government that the total number of fighters with the so-called Islamic State has dropped for the first time since 2014, to 19,000-25,000, give further weight to the claim that the group is in decline. But while this may offer hope to those who live under its sway, it does not significantly alter the threat to the international community. In fact, the reverse could be true. As the Islamic State loses ground in Syria and Iraq, it is likely to move resources to Libya and make further attempts to attack its enemies elsewhere. A video issued by the Islamic State this week makes a direct threat to the United States.

The opportunity for the Islamic State to carry out such threats may be limited, particularly in the U.S., where entry is difficult and vigilance is strong, but the attacks in Paris last November suggest both a determination to try and an ability to succeed. Significantly, at the same time as it noted an overall decline in Islamic State numbers, the U.S. government upped to 38,000 its estimate of the total number of foreigners who have joined the group since the start of the Syrian civil war, which compares to an upper estimate of 31,000 by The Soufan Group less than three months ago.  

Foreigners now dominate Islamic State ranks and, to some extent, offset the difficulties the group has faced in recruiting locals—seen in the rise in forced conscription, the clamping down on people attempting to leave areas under Islamic State control (which caused a minor riot in Fallujah earlier this month), and the increasing use of children in combat. But while the rise in foreign recruits may help the Islamic State in Iraq and Syria, a more significant question is how it might help the organization expand its campaign overseas.

The U.S. government believes that fighters have traveled to join the Islamic State from 120 countries. Compared to a total UN membership of 193, this is an extraordinary figure and suggests that the Islamic State's appeal resonates in every corner of the world. Although the number of recruits from some countries will be in the single figures, others will be in the thousands, and all countries will have to make some assessment of the threat these fighters pose to their own national security, particularly if they return

Estimates of the total number of recruits from specific countries and regions are never much more than informed guesses, but patterns are beginning to emerge. U.S. officials believe that about 7,000 nationals or residents of Western countries have joined the Islamic State since 2011, a figure that continues to inch up but has not changed dramatically over the last 12 months. Of these, roughly a quarter have died, half are still there, and the remainder have returned home or moved elsewhere. The UK government reckons over 300 are back in the country of the 800 who went; Germany puts its number of returnees at 270; France at 250; Canada at 60; Denmark at 50; the Netherlands at 40; Norway at 30; Spain at 25; Finland at 20, Switzerland at 13; and so on. On top of these figures are the increasing numbers sent home by Turkey before they could enter Syria, and those who wanted to go but never set off.

The total is alarming and presents a constant and growing challenge to national authorities in charge of counterterrorism, who naturally fear that increased numbers translate into an increased threat. Indeed, a senior police official in the UK warned this week that the Islamic State was planning a mass casualty attack in Great Britain, though he did not say why he believed that. However, it would be wrong to think that all returnees are equally dangerous. Many will have gone home disillusioned with the Islamic State, only too glad to disengage from the violence. The problem lies in knowing which ones are which.


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