Foreign Policy Research Institute A Nation Must Think Before it Acts Terror in Europe: Safeguarding U.S. Citizens At Home And Abroad

Terror in Europe: Safeguarding U.S. Citizens At Home And Abroad

Recent terrorist attacks in Paris, Istanbul and Brussels should not come as a surprise. The Islamic State’s rise in Europe has been more than four years in the making. By 2012, casual social media monitoring showed a large wave of young European men migrating through Turkey into Syria. When the Islamic State of Iraq (ISI) expanded to become the Islamic State of Iraq and the Levant (ISIL), they consolidated these Europeans into the largest foreign fighter force in history as part of the menace known today as the Islamic State.[1] Today, these jihadi combat veterans have logically begun returning home pursuing an unprecedented level of violence in the West on behalf of their Islamic State leaders.  

The Islamic State’s success arises both from the group’s aggressive pursuit of violence via enormous foreign fighter cadres and the West’s failures in preparing for the inevitable return of its angry young men. Assessing the risk to U.S. citizens from this current wave of Islamic State violence requires an examination of why the Islamic State has proven to be so effective in Europe and why European countries face such challenges in disrupting Islamic State terrorist networks.

Why has the Islamic State been so successful in Europe?

Al Qaeda desperately sought spectacular attacks in the West and in the case of the 7 July 2005 London bombings they achieved their goal. But their terrorist plots over a more than a decade never achieved the level of violence the Islamic State has attained in less than one year. While some have suggested the Islamic State is now pursuing an al Qaeda model in Europe, the Islamic State in many ways pursues an inverse approach to that of al Qaeda. Al Qaeda sought to recruit “Clean Skins” for the execution of their plots – Western passport holders without criminal records able to slip security and avoid detection in the lead up to an attack.[2] Al Qaeda ultimately recruited few of these “Clean Skin” recruits and even when they did, these operatives were deployed alone or in small groups toward unfamiliar targets. Once sent on missions, their recruits had limited training and combat experience. With the exception of the July 7, 2005 London attacks, their plots were routinely detected and disrupted. As seen in the Najibullah Zazi case in the U.S.[3], the U.K. transatlantic planes plot of 2006[4] and the failed follow on July 21, 2005 London attack[5], al Qaeda’s Western plotters struggled to construct explosive devices and their reconnaissance and communications were detected by intelligence and law enforcement.

The Islamic State’s massive cadre of trained European recruits and updated operational approach has sidestepped many of the challenges faced by al Qaeda. Unlike al Qaeda before them, the Islamic State has taken nearly every available European recruit into their ranks regardless of skill or previous criminal record. The Islamic State’s European foreign fighter cadres may certainly be ten times in number of al Qaeda before them. Islamic State recruits arrive to Syria alongside their relatives and friends extending physical relationships cemented in many years before in diaspora neighborhoods. The Islamic State’s recruits are more connected socially than ideologically, and their shared experience on the battlefield improves both their competency individually and their capability as an operational unit. While much has been made of their infiltration into Syrian refugee flows, many have returned home by using their passports and sliding back into neighborhoods filled with sympathetic supporters willing to join their ranks or assist in plots. In total, the scale, experience and cohesion of Islamic State foreign fighters in Europe is unprecedented.

The Islamic State also emits fewer signals by which counter terrorists can disrupt their attacks. Returning Islamic State foreign fighters plan attacks with greater autonomy than those al Qaeda plots from last decade hitting soft targets more than national monuments and government buildings. While al Qaeda micromanaged their Western plots, the Islamic State’s seasoned European cadres operate in areas they know well communicating less frequently and emitting fewer indicators law enforcement can detect. Their gun runs and use of suicide bombings mirror the style of Lashkar-­‐e-­‐Taiba’s 2009 attacks in Mumbai, India.[6]

Islamic State operatives’ communications back to headquarters are not only less necessary but benefit from a new era of encryption. The Islamic State has embraced social media and mobile applications to secure their communications as well as a range of computer programs that allow them to communicate freely without fear of detection.[7] Counterterrorists have few technical surveillance methods for detecting and disrupting these encrypted communications. The Islamic State’s operational approach and European foreign fighter legions are not following the al Qaeda model in Europe. They are instead forging a new playbook for Western terrorism incorporating lessons learned from a variety of terrorist groups around the world.

Why has Europe struggled in stopping Islamic State terrorism?

The Islamic State’s wide-­‐ranging European network has pushed European counterterrorists far past their capacity. In the Charlie Hebdo attack of January 2015, the Paris attacks of November 2015 and the Brussels attacks of March 2016, authorities knew many of the perpetrators. However, the vast array of investigative leads has clearly overwhelmed their systems.[8] There are far too many foreign fighters returning home requiring observation. Absent corroborating intelligence from signal intercepts and human sources, determining which terrorists to pursue has become a nearly random decision. Turkey, as compared to the rest of Europe, suffers from having both a large number of indigenous recruits and numerous foreign fighters, unable to return to their home countries, now residing inside their borders. Finally, the best recruiter of a future terrorist is a current terrorist. With so many experienced Islamic State members floating in diaspora communities, new local recruits, unable to reach Syria and Iraq, team up with Islamic State returnees. These new members prove harder for law enforcement and intelligence to detect as they lack prior records and have not tipped authorities off by traveling to join the Islamic State.

The European Union’s counterterrorism system is not only over capacity, but also of uneven capability. The United Kingdom (U.K.), France and Germany have a rich history of counterterrorism experience from which to draw expertise. The U.K., in particular, has invested sizeable resources over the last decade to improve their counterterrorism approach in the wake of the London bombings. However, many of the Islamic State’s foreign fighter legions have arisen from smaller European states, such as Belgium, not historically known for having vast numbers of jihadi volunteers. These smaller states not only lack the capacity to pursue a significant number of terrorism leads but often lack a dedicated counterterrorism force or robust intelligence services.[9]

Europol and Interpol provide valuable assistance and coordination, but they lack the investigative authority to pursue terrorism investigations across borders. An assortment of agencies across numerous jurisdictions executes Europe’s counterterrorism. Frank Cilluffo and Sharon Cardash of the Center for Cyber and Homeland Security at the George Washington University described how, “counterterrorism in Belgium is a highly local enterprise, where the mayor in essence calls the shots; and in Brussels alone there are 19 mayors.”[10] This extreme level of compartmentalization across the continent creates nearly endless barriers to information sharing and coordinated investigations. Cilluffo and Cardash go on to point out, “there is still much to be done to fuse relevant E.U. information systems (Schengen, visa, etc.) that were consciously designed and built as independent, largely in the interest of data privacy.”[11]

The European Union’s current configuration ultimately creates a counterterrorism patchwork. Countries commitments to counterterrorism on average remain too low. The uneven resource allocation and range of capacity now result in a massive deficit between terrorists and counterterrorists. The Islamic State’s terror cells can communicate and coordinate their operations at a rate far faster than European law enforcement and intelligence units can disrupt. Until this gap between terrorists and counterterrorists is closed, the Islamic State and those terrorist offshoots emerging in its wake will find Europe an enticing playground.

What’s the danger to U.S. citizens living and traveling in Europe?

The Islamic State, from a threat perspective, sees no difference between North America and Europe. They would equally enjoy the opportunity to bloody Westerners on either continent. The distinction between these two regional targets, from an Islamic State perspective, is access more than desire. The most obvious threat to Americans comes during their residence and travel in the European Union. As seen in Brussels, Americans living and traveling abroad died at both the airport suicide attack and in the Maelbeek subway station.

Islamic State violence and the resulting risk to Americans is two fold. First, Americans routinely traveling through transportation hubs and visiting locations popular with Westerners will, seemingly at random, be at risk. In both Paris and Brussels, the Islamic State hit a soccer stadium and a concert venue and is likely to strike any soft target where they can produce mass casualties. Barring advance warning provided through European intelligence or other sources, protecting Americans traveling through these attack locations will be nearly impossible to anticipate.

Second, American citizens, moving through Europe individually, provide a target of opportunity for Islamic State operatives unable to strike targets as collective cells. Counterterrorism pressure across the continent has increased and Islamic State operatives primed to attack may shift to killing or kidnapping single American citizens. Even before the Islamic State’s recent rise, U.S. service members were killed in Germany[12] and U.S. embassies and consulates were repeatedly attacked in Turkey.[13] The U.S. should expect more of these attacks. Issuing post attack travel warnings will prove completely insufficient in protecting American citizens from such events and a more aggressive approach is needed.

What’s the danger to the U.S. homeland from the Islamic State’s rise in Europe?

The U.S. enjoys the protection of two large oceans, which makes travel by Islamic State operatives significantly more challenging. Aside from the sheer distance between the U.S. and the Islamic State, the U.S. has invested heavily in screening programs at transportation hubs and borders since 9/11 strongly challenging terrorist efforts to infiltrate the homeland. However, the U.S. is not immune to Islamic State violence. The sheer volume of European Islamic State operatives and supporters, many of whom are not known to European authorities, make it possible that a determined terrorist could gain access to the U.S. via a tourist or student visa.

Lacking any previous intelligence and placement on a terrorist watch list, a European “Clean Skin” can in all likelihood slip into the U.S. undetected. These lone operatives and any potential partners may find greater challenge preparing and plotting an attack in the U.S. But, we must remember the Islamic State’s plots utilize less sophistication. Acquiring weapons in the U.S. is easier than in Europe, and its entirely conceivable an attacker could perpetrate a gun run on an American soft target with ease.

The greater threat to the U.S. from the Islamic State’s rise in Europe comes from those inspired by Paris and Brussels type attacks. The U.S. has witnessed only a trickle of American foreign fighters heading off to the Islamic State’s ranks and even fewer have returned. Rather than a directed plot by the Islamic State, the U.S. suffers from a rash of inspired Islamic State followers radicalized online with seemingly no direct connections to the group. These American online followers witness the success of Islamic State European attacks and feel embolden to duplicate their efforts in the U.S. homeland. Following the successful Paris attacks last November, the U.S. saw a spike in terrorist attacks and foiled plots. The San Bernardino massacre and the shooting of a Philadelphia police officer provide just two examples of how successful Islamic State directed European attacks rapidly cascade into inspired attacks in the U.S. with little or no direct connection back to the terror group.[14] A rash of disrupted inspired plots across the U.S. accompanied these two more notable attacks.[15]

The Islamic State in Europe: What should the U.S. do to protect its citizens?

Some might feel the U.S. can ignore Europe’s current terrorism crisis. But this would be mistaken, as many of these European partners have been essential allies dating back to the September 11 attacks of 2001. Standing by and watching Europe struggle at the hands of the Islamic State will only put the U.S. further at risk, both at home and abroad. The best defense of American citizens will come by helping Europe regain the counterterrorism initiative through aggressive counterterrorism investigations.

The U.S. should immediately assist the European Union in devising a cohesive strategy and supporting team to pursue Islamic State cells. Europe should convene an Islamic State counterterrorism task force focused on three objectives: stopping any impending Islamic State attack, destroying Islamic State facilitation and support networks, and disrupting Islamic State recruitment of homegrown extremists.[16] The essential ingredient for successful task force implementation will be the rapid increase and synchronization of European intelligence. The U.S. should offer any needed assistance to Europe in creating seamless information sharing across the continent. Over more than a decade, the U.S. has spent billions creating an intelligence sharing architecture and procedures for sharing information with international partners and domestically through the federal, state and local levels. U.S. lessons learned can accelerate E.U. information sharing improvements. The U.S. can also greatly assist by re-­‐doubling efforts to push intelligence to European partners who likely don’t have the sources or capability to quickly regain the initiative against the Islamic State.

The U.S. can also further protect its citizens by improving its risk assessment and warning systems. Currently, there is an unprecedented amount of open source information on foreign fighters from Europe. Foreign fighter records divulged by an Islamic State insider and research center studies of Islamic State recruitment patterns in Europe provide a good picture of European hotspots.[17] This data combined with recent attack patterns and investigative arrests should be utilized to create anticipatory models of potential terrorist activity in Europe. The results of this analysis should inform travel warnings for U.S. citizens prior to, not after, terrorist attacks.

In conclusion, above all else, the U.S. needs to undertake these European initiatives with speed. The Islamic State claims to have hundreds of operatives deployed to Europe. Even if their claims are exaggerated, their terrorist accomplishments in recent months suggest this current wave of terrorism will not end any time soon. The greatest future risk to U.S. citizens, at this point, comes from continued inaction against the Islamic State in Europe. The U.S. will play an essential role in reversing this trend.

[1] Clint Watts (22 March 2014) ISIS Rise After al Qaeda’s House of Cards. Foreign Policy Research Institute. Available at: house-of-cards-part-4-of-smarter-counterterrorism/

[2] Con Coughlin (9 April 2009) The Enemy Within Is Invisible. The Telegraph. Available at:

[3] A.G. Sulzberger and William K. Rashbaum. (22 Feb 2010) Guilty Plea Made In Plot To Bomb New York Subway. New York Times. Available at:

[4] (10 Aug 2006) Police: Plot To Blow Up Aircraft Foiled. CNN. Available at:

[5] (18 July 2015) July 21 London Bombings Fast Facts. CNN. Available at:

[6] Bruce Riedel (14 Nov 2015) Modeled On Mumbai? Why The 2008 India Attack is the best way to understand Paris. Brookings Institute. Available at: terrorism-riedel

[7] Rukmini Callimachi ( Mar 2016) How ISIS Built The Machinery Of Terror Under Europe’s Gaze. New York Times. Available at:

[8] Clint Watts (23 Mar 2016) A Wounded Islamic State Is A Dangerous Islamic State. Foreign Policy. Available at:

[9] Clint Watts (29 Mar 2016) The Islamic State in Europe: Terrorists Without Borders, Counterterrorists With All Borders. War On The Rocks. Available at: counterterrorists-with-all-borders/

[10] Frank J. Cilluffo and Sharon L. Cardash (31 Mar 2016) Beyond Brussels: Turning The Tide Against ISIL In Europe. War On The Rocks. Available at: europe/

[11] Ibid.

[12] (3 Mar 2011) Two U.S. airmen killed in German airport shooting. CNN. Available at:

[13] Yesim Dekmin and Seyhmus Cakan (10 Aug 2015) U.S. consulate in Turkey targeted as wave of attacks kills 9. Reuters. Available at:

[14] Dina Temple-Raston (16 Feb 2016) Analysts Parse Differences Between San Bernardino, Paris Attacks. NPR. Available at: bernardino-paris-attacks

[15] Program On Extremism (April 2016) ISIS In America: From Retweets to Raqqa. George Washington University. Available at:

[16] Clint Watts (29 Mar 2016) The Islamic State in Europe: Terrorists Without Borders, Counterterrorists With All Borders. War On The Rocks. Available at:

[17] International Center For The Study of Radicalization and Political Violence (ICSR) Western Foreign Fighters In Syria. Available at: fighters-syria/