In its initial report: Foreign Fighters in Syria, released by the Soufan Group in June 2014, it was estimated that approximately 12,000 foreign fighters from 81 countries had travelled there since 2011. Most joined the ranks of the Islamic State of Iraq and the Levant (ISIL), Jabhat al-Nusra, or Ahrar al-Sham.  

In a follow up report released by the Soufan Group just last week, it was estimated that those numbers more than doubled in the last 18 months to between 27,000 and 31,000 from 86 countries - a stark dose of reality that the foreign-fighter phenomenon has not only exploded in numbers but is global in nature.

Consider: The number of foreign fighters from Western Europe more than doubled in the last 18 months, from 2,500 in 2014, to over 5,000. Most of them come from just four countries - France with 1,700, the UK and Germany with 760 each, and Belgium with 470.

Report: Global effort to stop foreign fighters joining ISIL is failing

In Russia, those numbers have gone up three fold - from 800 in 2014, to 2,400 by September 2015 - most coming from Chechnya and Dagestan in the North Caucasus. According to Russian President Vladimir Putin, that number is as high as 5,000 to 7,000 when fighters from the former Soviet republics are included.

Startling numbers 

In North Africa and the Middle East the numbers are even more startling, with over 16,000 fighters having travelled to Syria and Iraq. Tunisians make up the largest contingent of foreign fighters overall, with an estimated 6,000. That's double the number from 2014. Saudi Arabians make up the next largest contingent with 2,500, followed by Jordanians with 2,000.


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Other countries in the region with significant numbers include Morocco - 1,200; Lebanon - 900; Libya - 600; Egypt - 600; and Algeria - 170.

The process of radicalisation and reasons for the foreign fighter flow to Syria and Iraq vary from region to region.

 

Turkey, too, has had its share of foreign fighters, with approximately 2,100 having gone to Syria and Iraq, although many of them have already returned home. According to Turkish authorities, 500 of its citizens have been imprisoned for joining ISIL, and another 100 for joining Jabhat al-Nusra.

Southeast Asia is not immune to the foreign fighter phenomena either. According to Indonesian officials, 700 of its citizens have fought in Syria and Iraq as of late 2015. In May 2014, they had reported that figure as being only 30 to 60.  

Compared to the dramatic increase in numbers of foreign fighters in Europe and elsewhere, the United States and Canada have remained relatively stable since 2014. According to FBI records, about 150 Americans have travelled to Syria as of September 2015, and another 100 have been arrested attempting to do so. Canadian officials report even less, with 130 of its citizens having gone to Syria as foreign fighters.  

Why they go

The process of radicalisation and reasons for the foreign fighter flow to Syria and Iraq vary from region to region. In North Africa, which has a long history of foreign fighters dating back to the Soviet occupation of Afghanistan in the 1980s, the deteriorating security situation, high levels of unemployment, and peer-to-peer recruitment by family, friends and influential members of the community are major factors.

In Europe, radicalisation and the foreign fighter flow are driven largely by a sense of marginalisation, writes Reardon [Reuters]

In Europe, radicalisation and the foreign fighter flow are driven largely by a sense of marginalisation and alienation among immigrant communities, particularly those from North Africa. French authorities categorise foreign fighters as disaffected, aimless and lacking a sense of belonging - traits that appear common from region to region.

Add to that equation community-based recruiting in European countries with the highest number of foreign fighters, where groups of acquaintances are drawn to a common identity.

Case in point: the Molenbeek neighbourhood of Brussels, where several of the terrorists from the November Paris attacks lived, and knew each other before joining ISIL in Syria, and then eventually making their way back home to carry out the attacks.


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For many foreign fighters, regardless of where they come from, their motivation is no more complex than a search for belonging, purpose, adventure, and friendship.

For many foreign fighters, regardless of where they come from, their motivation is no more complex than a search for belonging, purpose, adventure, and friendship.

 

What it means

The most troubling significance with these numbers is that despite a sustained international effort to contain ISIL and stem the flow of foreign fighters to Syria, they have more than doubled in just 18 months, indicating that ISIL's appeal has not ebbed - and in fact, may be stronger now than it was 18 months ago.

Another disturbing fact in all this is that the issue of foreign fighters is both a near-term threat and a long-term challenge. The Syrian civil war will not end soon, and although ISIL continues to be degraded through concentrated air strikes and military pressure on the ground, it will likely survive in one form or another for a considerable time.

In the meantime, new foreign fighters will continue to join its ranks, and many of those already there will return to their home countries where they pose a very real threat of either carrying out terrorists attacks on their own or at the direction of ISIL or other extremist groups.

For Western countries in particular, where 20-30 percent of foreign fighters return to their home countries, this presents a significant challenge to law enforcement agencies that must first identify them and then assess whatever threat they may pose.

The foreign fighter phenomenon in Syria goes well beyond the civil war there. No doubt, they have been a major factor - one of many - that have changed that country forever. But their impact goes beyond the borders of Syria.

Many will eventually or have already returned to their home countries, whether elsewhere in the Middle East, North Africa, Europe, Asia, North America or any of the 86 countries where they came from. Some will no doubt have had their fill of violence, and want nothing more to do with it.

But other returnees will no doubt be just as - or even more - radicalised and intent on carrying out terrorist attacks against their home countries, as we've already seen throughout the Middle East, North Africa and Europe.

And that's what makes the foreign fighter phenomenon such a dangerous and unpredictable double-edged sword - it kills and maims on both the down stroke in Syria and the upstroke abroad.

Martin Reardon is a senior vice president with the Soufan Group, a New York-based strategic security and intelligence consultancy, and senior director of Qatar International Academy for Security Studies. He is a 21-year veteran of the FBI and specialised in counterterrorism operations.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy. 

Source: Al Jazeera