Flows of foreign fighters to the current conflicts in Syria and Iraq are recent examples of a broader phenomenon that has seen tens of thousands of individuals travel to various conflict zones in the Middle East, North Africa, and elsewhere over the last three decades. In February 2015, the U.S. intelligence community assessed that more than 20,000 foreign fighters—including at least 3,400 Westerners—had traveled to the Syria-Iraq region since 2011. U.S. National Counterterrorism Center (NCTC) Director Nicholas Rasmussen has asserted that the numbers of those seeking to fight in Syria or Iraq are "unprecedented," that they "are going up," and that the majority of recent recruits are joining the Islamic State terrorist organization (also known as ISIL or ISIS). Among Western citizens who have become foreign fighters in Syria and Iraq in the last few years, the largest contingents are believed to be from countries in Europe. Some European estimates of foreign fighter flows (from official and unofficial sources) are higher than U.S. assessments, and suggest that upward of 4,000 or 5,000 Europeans may have traveled to the conflict zone. Smaller numbers of Americans, Canadians, and Australians have also sought to join the fighting. As of February 2015, U.S. officials estimated that more than 150 U.S. persons had traveled or attempted to travel to Syria to support armed groups there since the start of the Syrian conflict in 2011. There are no unclassified comprehensive figures available on how many Americans have joined the Islamic State organization relative to other armed groups, in part because the affiliation of many individuals is revealed only following their detention or death. While there is limited data that would allow a definitive assessment of the threat posed by individuals who have traveled to Iraq, Syria, or elsewhere as foreign fighters, U.S. officials have noted that there is a risk that "these individuals may eventually return to their home countries battle-hardened, radicalized, and willing to commit violence." Such fears have been heightened considerably by the January 2015 terrorist attacks in France, in which at least 17 people were killed over the course of several days in three related incidents that targeted the Paris headquarters of the French satirical magazine Charlie Hebdo , police officers, and a kosher supermarket. The perpetrators of the attacks were French-born Muslims; at least one suspect reportedly traveled to Yemen in 2011 for terrorist training, while another pledged allegiance to the Islamic State group. Prior to the Paris attacks, the May 2014 murder of four people at the Jewish Museum in Brussels, Belgium—allegedly carried out by a French Muslim who had spent a year with Islamist fighters in Syria—also raised alarm bells in both Europe and the United States about returning fighters. In addition, security services in Western countries are increasingly concerned that some citizens and residents may be inspired by Islamist extremist propaganda to commit attacks at home without ever traveling abroad. Many point to the two separate attacks in Canada in October 2014, which targeted members of the armed forces and the Canadian Parliament, and the hostage-taking incident in Sydney, Australia, in December 2014, as worrisome examples of "lone wolf" attacks carried out by "self-radicalized" Muslims. Fears of "copycat" incidents have also increased following the February 2015 shootings in Copenhagen, Denmark, in which a gunman killed two individuals and wounded several police officers at two separate locations—a cafe hosting a free speech discussion and a synagogue—broadly mirroring the Paris attacks. The suspect, a young Danish-born citizen of Palestinian descent, appears to have been radicalized in prison and may have been interested in traveling to fight in Syria or Iraq. U.S. and European officials further note the potential propaganda value of Western Muslims engaged in fighting in Iraq or Syria. Some analysts have speculated that the Islamic State group may view Americans or other English speakers as particularly useful for targeting potential recruits in Western countries. Western fighters have appeared in several Islamic State propaganda videos. Intelligence services believe that the beheadings of three Americans and two United Kingdom citizens between August and November 2014, videotaped and posted online, were carried out by a British member of the Islamic State organization. Some intelligence officials have also suggested that the Islamic State group recruits Americans and other Westerners specifically for their presumed ability to reenter the United States and Europe with less scrutiny. The United States has close, long-standing bilateral law enforcement and intelligence relations with most European countries. Since the September 11, 2001 terrorist attacks, the United States and the 28-member European Union (EU) have also worked to enhance their counterterrorism and homeland security cooperation. In recent years, U.S. and European policymakers have sought to exchange "best practices" on ways to prevent radicalization, counter violent extremism (CVE), and tackle the potential foreign fighter threat. The United States and European governments also worked together to pass U.N. Security Council Resolution 2178 in September 2014, which seeks to combat the foreign fighter phenomenon worldwide. In the wake of the Paris attacks, the White House convened a "Summit on Countering Violent Extremism" on February 17-19, 2015, in Washington, DC. This three-day event featured discussions with U.S. community leaders, civil society groups, and law enforcement officials on domestic CVE efforts, as well as talks with U.S. business and technology leaders on tackling radicalization online. The summit also included an international component in which representatives from over 60 countries (including the mayor of Paris and other high-ranking European and EU officials) discussed preventive measures and shared "best practices." U.S. officials and analysts contend that the potential foreign fighter threat underscores the importance of close law enforcement ties with key European allies and existing U.S.-EU information-sharing arrangements, including those related to tracking terrorist financing and sharing airline passenger data. Some U.S. policymakers, including several Members of Congress, have expressed particular worries about European fighters in Syria and Iraq because of the U.S. Visa Waiver Program (VWP). The VWP permits short-term visa-free travel to the United States from 38 countries, most of which are in Europe (see Appendix A ). In July 2014, U.S. Attorney General Eric Holder asserted during a speech in Norway, that "We have a mutual and compelling interest in developing shared strategies for confronting the influx of U.S. and European-born violent extremists in Syria. And because our citizens can freely travel, visa-free ... the problem of fighters in Syria returning to any of our countries is a problem for all of our countries." Hearings in the 113 th and 114 th Congresses have addressed the potential foreign fighter threat, and several pieces of legislation have been introduced on the VWP. While some Members of Congress appear to support limiting or suspending the VWP, others indicate a preference for strengthening its existing security controls. The Obama Administration continues to support the VWP as a key facilitator of transatlantic trade and tourism. In November 2014, however, the U.S. Department of Homeland Security announced that VWP travelers would be required to submit additional advanced biographic information to enable more accurate and comprehensive screening because of the possible dangers posed by foreign fighters. This report discusses U.S. and European assessments of and responses to the foreign fighter phenomenon. It focuses on government policies primarily in Western European countries and analyzes EU measures to counter the foreign fighter threat given the EU's largely open internal borders and that 23 EU member states belong to the U.S. Visa Waiver Program. It also briefly evaluates foreign fighter outflows and responses in the Western Balkans and Russia. The report concludes with a discussion of U.S.-European cooperation, primarily in the law enforcement and intelligence areas, and addresses issues of particular concern for Congress, such as the VWP. Conflicts in Syria and Iraq have attracted thousands of individuals from dozens of countries to fight alongside a broad spectrum of armed groups over the last 10 years. In Iraq, the anti-U.S. insurgency and the outbreak of sectarian warfare drew thousands of fighters to the country, particularly during 2003 to 2008, and predominantly from the Arab countries of the Middle East and North Africa. Iran supported Shiite militia groups during this period. While the vast majority of insurgent operations in Iraq were carried out by Iraqis, Sunni foreign fighters actively participated in fighting against U.S. forces, and some sources suggest that foreigners disproportionately were employed by some Sunni insurgent forces—including antecedents of the Islamic State organization—in suicide bombings and other high-profile attacks. In 2008, U.S. military sources estimated that foreigners made up roughly 10% of the personnel of the Islamic State of Iraq (also known as Al Qaeda in Iraq, the predecessor to the Islamic State), who were then estimated to have declined from as many as 10,000 fighters to roughly 2,000 to 3,000 fighters. These sources further reported that, in 2008, foreigners constituted roughly 1% of the 23,000 detainees in U.S. custody in Iraq. U.S. officials accused the Syrian government of President Bashar al Asad of facilitating the flow of foreign fighters through Syria into Iraq during this period, and the U.S. military reportedly took action inside Syria in at least one instance in part to disrupt such flows. An outflow of foreign fighters from Iraq increasingly was reported by the international media from 2008 onward. In subsequent years, some governments in the Middle East and North Africa took steps to prosecute, monitor, and/or rehabilitate foreign fighters and individuals who facilitated their travel to Iraq, with varying outcomes. The unrest and conflict that began in Syria in 2011 reinvigorated the flow of foreign fighters to the area, and transnational networks active in sending fighters to Iraq reportedly reactivated and adapted their operations to send recruits to insurgent groups fighting the Asad government in Syria. By February 2014, U.S. Director of National Intelligence (DNI) James Clapper publicly assessed the overall strength of the insurgency in Syria at "somewhere between 75,000 or 80,000 or up to 110,000 to 115,000 insurgents, who are organized into more than 1,500 groups of widely varying political leanings." According to then-National Counterterrorism Center (NCTC) Deputy Director Nicholas Rasmussen, "Syria remains the preeminent location for independent or Al Qaeda-aligned groups to recruit, train, and equip a growing number of extremists, some of whom we assess may seek to conduct external attacks." NCTC also has acknowledged that Islamic State sympathizers "could conduct a limited, self-directed attack here at home with no warning," but that "any threat to the U.S. homeland from these types of extremists is likely to be limited in scope and scale." Further explication from U.S. government sources of the nature and scale of such a threat is generally unavailable from unclassified sources. As noted previously, U.S. authorities judge that more than 20,000 foreign fighters have traveled to the Syria-Iraq region since the start of the conflict in Syria in 2011; of this figure, at least 3,400 are believed to be Westerners, including roughly 150 Americans. U.S. officials suggest that foreign fighters in Syria and Iraq hail from more than 90 countries. Roughly 10,000 foreign fighters are thought to have joined the Islamic State group, according to U.S. Special Presidential Envoy for the Global Coalition to Counter ISIL, General John Allen. More detailed U.S. government assessments of the national origins and current organizational affiliations of foreign fighters in Syria have not been made publicly available. U.S. officials estimate that a handful of Americans have died fighting in the Syrian conflict since 2012. They also assert that military operations against the Islamic State group since August 2014 have killed thousands of fighters, including an unknown number of foreigners. In general, nongovernment open-source analyses available as of early 2015 are close to U.S. government public estimates of the size, general make-up, and affiliations of foreign fighters in Syria. Figures released in January 2015 by the London-based International Centre for the Study of Radicalisation and Political Violence (ICSR) suggest that more than 20,000 foreign fighters have traveled to Syria and Iraq, with as many as 11,000 from the Middle East, 3,000 from the countries of the former Soviet Union, and up to 4,000 from Western Europe. Such independent assessments also indicate that the flow of foreign fighters to Syria since 2011 has been unprecedented in terms of its scope and speed relative to other comparable conflicts. Echoing these analyses, in September 2014, then-NCTC Deputy Director Rasmussen testified before Congress that, "The rate of travelers into Syria exceeds the rate of travelers who went into Afghanistan/Pakistan, Iraq, Yemen, or Somalia at any point in the last ten years." Information released by insurgent groups in Syria suggests that foreign fighters have affiliated themselves with entities drawn from across the ideological spectrum of opposition groups described by U.S. officials. However, open sources strongly suggest that a plurality if not a majority of foreign fighters active in Syria have affiliated themselves with armed Islamist groups, including U.S.-designated Foreign Terrorist Organizations such as Jabhat al Nusra and the Islamic State. Many groups in Syria, which range from relatively moderate to more extreme in ideology and action, have issued appeals for foreign support and have utilized foreign fighters (see Appendix B for more information on foreign fighter recruitment). Some debate exists regarding the utility of foreign fighters to local groups, however. Foreigners may face language barriers and difficulties integrating with local populations or group members of other nationalities. Like other foreign fighters, the roles that Americans play in these organizations are likely to vary depending on an individual's skills and/or the needs of the group. In a December 2014 interview, General Allen stated that foreign fighters who lack military qualifications often become suicide bombers. Syrian government forces also have been bolstered by support from thousands of Lebanese Hezbollah personnel along with an unknown number of Iraqi Shiite militia members. In addition, U.S. officials have accused the government of Iran of deploying members of its security services to Syria in support of the Asad government. At least one source asserts that some Asad regime air strike missions may be piloted by Russians. Various nongovernmental assessments have analyzed the makeup and activities of foreign fighter contingents in Syria from a number of different countries. These assessments reveal a range of historical and current patterns of recruitment, travel, group dynamics, and engagement in combat. Nevertheless, independent open source analyses of so-called "martyrdom" (death) notices, self-reported insurgent operations material, individuals' social media postings, foreign government estimates, and international press sources provide only limited information on the backgrounds and affiliations of some recent foreign fighters in Syria. Individual accounts of foreign fighters' travel to Syria and Iraq suggest that potential recruits use both direct and circuitous routes to make their way to the conflict zone. While it appears that some individuals seek to mask their intended destinations and means of travel, others do not. Many foreign fighters, especially from Europe, reportedly travel through Turkey en route to opposition-held areas of northern Syria and Iraq. Turkey's multiple air connections and its long border with Syria that spans remote and in some places mountainous terrain have made Turkey a key transit location for fighters bound for Syria and Iraq. U.S. officials from the intelligence community, State Department, and agencies concerned with domestic security assess, monitor, and respond to threats posed by foreign fighters active in Syria and Iraq. Diplomatic and intelligence efforts focus on coordinating with source, transit, and returnee destination countries to strengthen shared responses and preventive measures. In March 2014, the State Department named Ambassador Robert Bradtke as " senior adviser for partner engagement on Syria foreign fighters." According to a department spokesperson, Ambassador Bradtke was charged with leading "a comprehensive effort, including marshalling representatives from a number of U.S. departments and agencies, to encourage key European, North African, and Middle Eastern partners to prioritize the threat, address vulnerabilities, and adapt to—and prevent—foreign fighters." Testifying before the House Foreign Affairs Committee in December 2014, Ambassador Bradtke laid out seven areas in which the United States is engaging with regional partners in order to counter foreign fighters: Information - sharing . The United States is working bilaterally to bolster information sharing on known and suspected terrorists and called on partners to make greater use of multilateral arrangements for sharing information, such as Interpol's Foreign Fighters Fusion Cell. Law enforcement cooperation . The United States is assisting local law enforcement authorities in partner countries to bring suspected terrorists to trial. Capacity- building . The United States is working with partner countries to strengthen their infrastructure, including through stronger counterterrorism legislation and improved interagency coordination. Halting external financing . The Treasury Department is working with regional partners to identify cases in which individuals or organizations are raising funds to support the Islamic State or other terrorist groups. Counter-messaging . The United States has sought to counter the Islamic State's message (and that of other terrorist groups) by using social media, including efforts led by the State Department's Center for Strategic Counterterrorism Communications. Countering violent extremism . The United States is sharing its experience with countering violent extremism programs and working with partners to build their capacity to implement similar programs. Border and aviation security . The United States is implementing measures, including increased screening and preclearance at overseas airports, and enhancements to the Electronic System for Travel Authorization and the Visa Waiver Program (see "Issues for Congress" for more information). The United States has also sought to address the potential foreign fighter threat through the United Nations. In August 2014, the U.S. government supported the adoption of U.N. Security Council Resolution 2170, which strengthened international sanctions designed to combat the Islamic State group, Jabhat al Nusra, and Al Qaeda-affiliated entities. The resolution calls upon all U.N. member states "to take national measures to suppress the flow of foreign terrorist fighters to, and bring to justice, in accordance with applicable international law, foreign terrorist fighters of, ISIL, ANF [Jabhat al Nusra] and all other individuals, groups, undertakings and entities associated with Al Qaeda." Resolution 2170 also reiterates member states' obligation to prevent terrorist travel, limit supplies of weapons and financing, and exchange information on the groups. On September 24, 2014, President Obama led a session of the U.N. Security Council focused on strengthening international responses to the threat posed by foreign fighters traveling to conflict zones, especially in Syria and Iraq. The session concluded with the adoption of U.N. Security Council Resolution 2178, which requires U.N. member states, consistent with international law, to "prevent and suppress the recruiting, organizing, transporting or equipping of individuals who travel to a State other than their States of residence or nationality for the purpose of the perpetration, planning, or preparation of, or participation in, terrorist acts or the providing or receiving of terrorist training, and the financing of their travel and of their activities." In particular, U.N. Security Council Resolution 2178 calls on all U.N. member states to ensure the ability in their domestic laws to prosecute and penalize their nationals and others departing their territories for foreign fighter-related crimes. In December 2014, Ambassador Bradtke asserted to Congress, "Several countries have already enacted or proposed legislation to permit such prosecution; other countries have stepped up their enforcement of existing laws. We continue to urge partners to meet their obligations under UNSCR 2178, and are offering assistance to partners who may need help in doing so." U.N. Security Council Resolution 2199, adopted on February 12, 2015, reaffirms several requirements to restrict flows of arms, combat financing, and prevent trade in Syrian and Iraqi cultural property; it also establishes a reporting mechanism on international implementation of existing related resolutions, including the foreign fighter-related provisions in UNSCR 2178. Like the United States, European governments and the 28-member European Union (EU) have become increasingly alarmed by recent events in Syria and Iraq, especially the threat posed by the Islamic State organization to both regional stability and domestic security. EU leaders have asserted that "the creation of an Islamic Caliphate in Iraq and Syria and the Islamist-extremist export of terrorism on which it is based, is a direct threat to the security of the European countries." Given the growing number of European citizens or residents of Muslim background fighting in the conflict zone, security services have become steadily more concerned about the potential danger such trained militants might pose if and when they return to Europe. Worries also exist about "lone wolf" attacks from those who may not have traveled abroad but have been inspired by Islamist extremist propaganda. Several incidents over the last year have heightened such fears, including The May 24, 2014, murder of four people at the Jewish Museum in Brussels, Belgium. This attack was allegedly carried out by a French Muslim who had spent a year with Islamist fighters in Syria. Security officials assert that the suspect may have been associated with the Islamic State organization. The beheadings of three Americans and two UK citizens between August and November 2014 by a suspected British member of the Islamic State group. The January 7, 2015, attack in Paris, France that targeted the office of French satirical magazine Charlie Hebdo and subsequent related incidents on January 8-9 that targeted a police officer and a kosher market. Seventeen people in total died in the attacks. The three perpetrators were French-born Muslims, with possible ties to Al Qaeda in Yemen and the Islamic State organization. The January 15, 2015, police raids in Belgium against a suspected Islamist terrorist cell believed to be planning an imminent attack, reportedly targeting police officers. Two suspects (both Belgian citizens of Muslim background) were killed during the raids by police in Verviers, near the German border; 13 others were arrested throughout the country as part of the alleged plot. The February 14-15, 2015, shootings in Copenhagen, Denmark, in which a Danish Muslim is believed responsible for killing two individuals, one at a cafe hosting a discussion on free speech with a controversial Swedish cartoonist and another at a synagogue; five police officers were also wounded in the attacks. Although it is difficult to assess the precise number of Muslims from Europe who have joined rebel or extremist groups in Syria and Iraq, European officials believe that their ranks have been increasing, with more European Muslims fighting in the current conflict than in previous ones. As of early January 2015, estimates from Europol, the EU's joint criminal intelligence body, suggest that at least 3,000 and upward of 5,000 EU citizens have left Europe to fight in Syria, Iraq, and other conflict zones. As noted earlier, a January 2015 study by the International Centre for the Study of Radicalisation and Political Violence (ICSR) indicates that up to 4,000 individuals from Western Europe have traveled to Syria and Iraq to join the fighting (roughly double the Centre's December 2013 projections). As seen in Figure 1 , key European countries of origin reportedly include Austria, Belgium, Denmark, France, Germany, the Netherlands, Spain, Sweden, and the United Kingdom. The conflict in the Syria-Iraq region has also attracted fighters from Turkey and countries with majority Muslim populations in the Western Balkans (especially Albania, Bosnia, and Kosovo), as well as from Muslim communities in Russia and other parts of the former Soviet Union. Experts assert that many fighters from Europe have become associated with Islamist extremist groups opposing the Asad regime, including the Islamic State as well as the Al Qaeda-affiliated Jabhat al Nusra. While European Muslims who have gone to fight in Syria or Iraq may already have been radicalized to some extent at home, authorities worry that fighters may return not only with more extremist views but also with enhanced training and weapon skills. Some studies suggest that returned Muslim fighters are more likely to commit acts of violent extremism than Muslims in the general population, and that their attacks are more lethal than those carried out by individuals who lack fighting or training experience abroad. At the same time, analysts question how widespread the threat is, noting that only a small proportion of foreign fighters have actually committed acts of violence upon returning to their home countries. Experts also point out that many Europeans who have gone to fight in countries such as Iraq or Syria may have done so in part because of feelings of disaffection with Western societies and have no plans to return home, while others have been or will be killed. Furthermore, some European fighters may return traumatized and disillusioned by the brutality of the conflict and have no intention of committing violence at home. European governments have been addressing security concerns raised by European fighters with a wide array of measures, including increasing surveillance, combating terrorist recruitment, prohibiting travel, detaining returning fighters, and bolstering counterterrorism legislation. Individuals suspected of having traveled to fight in Syria or Iraq, planning such travel, or recruiting others have been arrested in Belgium, France, Germany, the Netherlands, Spain, and the United Kingdom (among other countries) on a range of different terrorism charges. Some of these governments, such as France, Germany, the Netherlands, and the United Kingdom, have also sought to stop citizens or residents from traveling to the Syria-Iraq region under rules that permit the confiscation of passports or travel identification documents on security grounds. In addition, several European governments are considering strengthening existing anti-terrorism legislation to ensure that their laws permit prosecuting those who travel or attempt to travel abroad for terrorist purposes (often termed informally as "jihadi travel"), as required by U.N. Security Council Resolution 2178 of September 2014. European policymakers are also seeking ways to combat radicalization and extremist propaganda, especially on the Internet and social media. Over the last decade, most European governments have developed counter-radicalization initiatives, although they vary in intensity; Denmark, the Netherlands, Norway, and the United Kingdom are recognized as having some of the most comprehensive programs. European officials and analysts contend that efforts to prevent radicalization and encourage de-radicalization are crucial to the fight against violent extremism, especially in Muslim communities, and must be undertaken at the national and local levels, in partnership with community and civil society groups. Given the role that information technology and the Internet now play in the ability of Islamist extremists to communicate their ideology, particularly among tech-savvy youth, some European governments are increasingly focused on developing online counter-narratives and working with Internet and social media companies to limit or remove radical content. As European countries struggle to address the potential threat posed by returning fighters, a debate has arisen over the proper balance between security measures and "softer" approaches that promote de-radicalization and rehabilitation. Some experts caution against automatically pursuing criminal charges against all returnees, noting that prisons often serve as fertile recruiting grounds for Islamist extremists. Two of the perpetrators in the January 2015 attacks in Paris, as well as the suspect in the February 2015 attacks in Copenhagen, are believed to have been radicalized in prison. EU Counterterrorism Coordinator Gilles de Kerchove has asserted that incarcerating all returning fighters would be an "invitation" to further radicalization; he called for authorities to distinguish between hardened fighters and those who return traumatized or disillusioned, and for rehabilitation programs both inside and outside prisons. Some commentators point to a program in Aarhus, Denmark, which seeks to rehabilitate returning fighters—helping them find jobs or attend school—and more broadly aims to improve Muslim integration, as a possible successful model; local officials also attribute such efforts to significantly decreasing the number of youths from Aarhus leaving to fight in Syria or Iraq. Despite these efforts, finding ways to stem the flow of European fighters to the Syria-Iraq region and keep track of those who go and return remains challenging. European governments face budgetary and personnel resource constraints in seeking to identify and monitor a growing number of potential assailants. Prosecuting individuals preemptively is difficult in many European countries because most existing laws require a high level of proof that a suspect has actually engaged in terrorism abroad or has returned to commit a terrorist act. Certain tools for preventing travel, such as confiscating passports, can entail lengthy legal processes. Analysts also note that while some European countries have laws that restrict so-called "jihadi travel," others do not yet. Consequently, national efforts by some European governments to stop such travel could be impeded by participation in the Schengen area of free movement, to which most European countries belong, and which permits individuals to travel without passport checks among participating states. For example, a French citizen could circumvent French travel restrictions to Syria or Iraq by leaving and reentering Europe from another EU country without such restrictions, and then traveling back to France. Given the Schengen system and the EU's largely open internal borders, many analysts contend that steps must be taken at the EU level to better combat the potential threat posed by European fighters. Those of this view argue that an EU-wide approach is especially necessary to increase intelligence-sharing among the bloc's 28 member states and to harmonize national criminal laws (especially on "jihadi travel"). The EU has been working on a range of measures to address the foreign fighter phenomenon, but reaching agreement among member states and between EU institutions on certain initiatives—such as establishing an EU-wide system for the collection of airline passenger name record (PNR) data—has been difficult. Over the past two years, the 28-member EU has paid significant attention to the possible foreign fighter threat, with the issue figuring prominently at numerous high-level EU ministerial meetings. Although the primary responsibility for countering terrorism lies with individual member states, EU leaders have long recognized that the Union can and should play a supportive role in responding to the cross-border nature of terrorist threats. EU efforts since 2013 have focused broadly on preventing the flow of foreign fighters to Syria and Iraq, improving information exchanges and the detection of foreign fighter travel, ensuring an adequate criminal justice response throughout the EU, enhancing counter-radicalization strategies, and engaging more closely with third countries. Despite the EU's political commitment, however, some experts suggest that concerns about protecting national sovereignty, data privacy, and civil liberties have slowed progress on some measures. The terrorist attacks in Paris and Copenhagen in early 2015 have injected greater urgency and momentum into EU initiatives to combat the foreign fighter phenomenon. At the EU's informal heads of state and government meeting on February 12, 2015, leaders outlined several key goals to guide EU work in the near term. These include the following: enhancing information-sharing among member states and with EU bodies such as Europol (the EU agency that handles criminal intelligence) and Eurojust (the EU agency responsible for prosecutorial coordination in cross-border crimes); finalizing an EU-wide system for the collection of airline Passenger Name Record data to help counter terrorist threats and improve information exchanges among EU member states; strengthening external EU border controls by making full use of existing security tools provided in the framework that governs the Schengen area of free movement; preventing radicalization by detecting and removing Internet content that promotes terrorism or extremism, developing communication strategies to foster tolerance and counter terrorist ideologies, and addressing societal factors and situations in prisons that may contribute to radicalization; implementing strengthened EU rules to prevent money laundering and terrorist financing; increasing cooperation to curb the illicit trafficking of firearms given that the recent terrorist attacks in Paris and Copenhagen appear to have been carried out with military-grade weapons that are illegal in most European countries; and improving cooperation with international partners, especially in the Middle East, North Africa, the Sahel, and the Western Balkans. In March 2015, EU justice and home affairs ministers directed Europol to establish a new EU Internet Referral Unit to help combat radicalization and violent extremism online. This unit is expected to monitor terrorist content on the Internet and social media platforms and work with service providers to flag and remove such content. EU policymakers have been holding discussions with Internet and social media companies, such as Google, Twitter, and Facebook, to explore what more can be done to tackle radicalization and counter jihadist propaganda online. EU leaders called for the new Internet Referral Unit to be operational by July 2015. Beside the work at EU level, a group of EU member states most affected by the foreign fighter phenomenon (the so-called "Group of Nine") have been meeting regularly since 2013 under the leadership of Belgium (and now France) to share information on the nature of the threat, compare policy measures, and discuss intensified European cooperation. In July 2014, most of these countries agreed to an "action plan" broadly aimed at stopping Europeans from going to fight in Syria and Iraq, improving the monitoring of returning European fighters, and increasing information exchanges. European officials assert that many of the initiatives discussed in the "Group of Nine" have since been taken up at EU level. As noted earlier, however, forging common EU policies to counter the potential foreign fighter threat has been challenging. Establishing an EU-wide PNR system has been under discussion for years, but a proposal originally put forward in 2011 has been stalled since 2013 in the European Parliament—a key EU institution—because of data privacy concerns (see text box for more information). Political pressure to adopt an EU PNR system has intensified significantly following the January 2015 attacks in Paris. EU governments assert that an EU-wide PNR system is particularly crucial to helping law enforcement authorities identify previously unknown suspects. EU officials also argue that some member states have already established, or are working on establishing, their own national PNR collection systems and that finalizing the EU PNR proposal is necessary to ensure harmonization across the EU on PNR collection, usage, and data protection practices. In February 2015, the European Parliament passed a resolution on anti-terrorism measures and pledged to work toward finalizing a revised PNR proposal by the end of the year. Nevertheless, observers caution that various Members of the European Parliament (MEPs) believe that a revised PNR proposal—also presented in February 2015—could still infringe too much on the right to privacy and other fundamental rights. Objections focus in particular on the PNR proposal's blanket retention of data and the length of time the data would be retained. Some influential MEPs argue that greater attention instead should be placed on improving intelligence-sharing among European law enforcement authorities and assert that while the PNR proposal mandates the collection and retention of PNR data, it does not go far enough in ensuring that it is meaningfully shared. MEPs may also seek to link approval of the PNR proposal to progress on controversial EU data protection reforms under discussion since 2012. Other potentially key ideas—such as harmonizing national laws to make traveling abroad for terrorist purposes a criminal offense in all 28 EU countries, or increasing intelligence-sharing to track extremists leaving for and returning from the Syria-Iraq region—are among the most difficult for the EU to agree upon and implement. This is largely because such measures relate to police and judicial issues long viewed as central to a nation-state's sovereignty. In December 2014, EU justice and home affairs ministers decided to consider revising the EU's Framework Decision on Combating Terrorism—which sets out a common EU definition of terrorism and common criminal penalties—in light of U.N. Security Council Resolution 2178 that calls on all U.N. member countries to ensure that their laws permit the prosecution of foreign fighter-related offenses. Presently, the EU's common definition does not specifically criminalize traveling or attempting to travel abroad for terrorist purposes, nor the receiving of terrorist training. While some EU member states have created such offenses already in their criminal codes, others have not yet done so. EU officials recognized the need to ensure that all EU member states fully comply with the provisions of UNSCR 2178. However, some EU governments initially appeared hesitant to consider amending the EU's common terrorism definition. They argued that implementing UNSCR 2178 could be done more quickly at the national level given that harmonizing criminal laws across the EU is often arduous because of varying national prerogatives on crime and punishment and concerns that EU-wide measures could infringe on national legal systems. Other member states and some EU policymakers countered that explicitly criminalizing foreign fighter-related offenses in the common definition would help avoid prosecution gaps and facilitate cross-border law enforcement and judicial cooperation in the longer term. Past ideas to enhance EU-wide intelligence capabilities or create a centralized EU intelligence agency have also foundered on sovereignty issues. The EU has a small Intelligence Analysis Center (INTCEN) to provide analysis, early warning, and situational awareness to EU institutions and member states in the fields of security, defense, and counterterrorism, but INTCEN does not have collection capabilities or the ability to conduct clandestine operations. Despite the Paris and Copenhagen attacks, the EU is not expected to pursue any significant changes to INTCEN's mandate. Some member states may view even limited information-sharing measures focused on foreign fighters and returnees as potentially compromising national intelligence sources or methods. EU officials have been encouraging member states to make greater use of existing common databases to help keep better tabs on foreign fighters and returnees. Such databases include the Schengen Information System (SIS)—which contains information on suspected criminals, forged identity documents, and stolen vehicles and property—and Europol's Focal Point Travellers database, established in 2013 to collect and analyze information on suspected European fighters. However, these databases depend on receiving information from member state law enforcement authorities and can only be effective EU-wide tools if national police and intelligence agencies provide them with relevant information. EU Counterterrorism Coordinator Gilles de Kerchove contends that while member states have begun providing more information to Europol's Focal Point Travellers database, the amount of data provided continues to fall short of expectations; reportedly, just four EU members contribute 80% of the data to Focal Point Travellers. Strengthening external EU border controls has also been somewhat controversial as EU leaders seek to balance enhancing security with protecting the fundamental right of European citizens to the freedom of movement. Some press reports indicate that only about 30% of passports presented by travelers entering or leaving the Schengen area are checked electronically to see if they are lost, stolen, or counterfeit. The European Commission (the EU's executive) has been encouraging member states to increase electronic checks at the EU's external borders. EU leaders have also agreed to "systematic" checks against relevant law enforcement databases of EU citizens flagged as possible terrorist suspects or returning fighters at the external borders. However, the EU has stopped short (for now) of heeding the demands of some member states (including France and Spain) to amend the Schengen Borders Code—the detailed set of rules governing both external and internal border controls in the Schengen area—to permit more extensive checks of EU or other Schengen country nationals at the external borders. The European Commission and the European Parliament largely oppose any changes to the Schengen Borders Code. They fear that some European countries and populist politicians would use any possible revision process of the external border control rules as an opportunity to push for re-imposing internal border controls as well. The Commission and the Parliament maintain that Schengen's current rules provide enough flexibility to enhance external EU border controls and better combat the potential foreign fighter threat. Over the last two years, the Belgian government has become increasingly alarmed about the growing number of European citizens or residents of Muslim background fighting in Syria and Iraq and the potential dangers that returning fighters may pose. Fears in Belgium have been especially acute since the May 24, 2014, attack in which four people were shot and killed at the Jewish Museum in Brussels. This attack was allegedly perpetrated by a French Muslim who had spent the past year with Islamist fighters in Syria; French and Belgian officials assert that the suspect may have been associated with the Islamic State organization. On January 15, 2015, Belgian authorities broke up a terrorist cell believed to have been planning an imminent attack, reportedly on Belgian police officers. Two suspects (both Muslims) were killed in Verviers, an eastern town near the German border; one of those killed was a Belgian national, the other held dual Belgian-Moroccan citizenship. Thirteen other individuals were detained throughout Belgium in connection to the plot; several of those arrested may have traveled to and returned from Syria. Following these raids, Belgium also deployed roughly 300 troops in Brussels and Antwerp to guard sensitive locations, including Jewish sites, embassies, and the headquarters of the European Union (which is based in Brussels). Over 600,000 Muslims live in Belgium, comprising 5%-6% of Belgium's total population of roughly 11 million. Many Muslims in Belgium are the children or grandchildren of immigrants from North Africa (especially Morocco, Tunisia, and Algeria) or Turkey. Belgian authorities assert that as of early 2015, about 380 Belgians have tried to leave in order to fight in Syria and Iraq and that 330 have succeeded in doing so; official sources also estimate that 180 individuals from Belgium are in the region or en route, and that approximately 50 have died in the conflict. Some independent studies assess that the number of Belgians who have traveled or attempted to travel to the Syria-Iraq region is slightly higher; recent estimates from the International Centre for the Study of Radicalisation suggest that up to 440 Belgians may have joined the fighting in Syria and Iraq. Both official and unofficial sources indicate that Belgium has one of the highest number of foreign fighters per capita of any European country. Some observers describe Belgium as having a "well-developed underground jihadist pipeline." Belgian law enforcement has focused on Sharia4Belgium, an extremist Islamist group, as a key recruiter of fighters for Syria and Iraq. Now banned, Belgian officials estimate that 10% of Belgians fighting in Syria and Iraq had links to Sharia4Belgium. In February 2015, 45 members of Sharia4Belgium were convicted by a court in Antwerp of terrorism-related offenses. The group's leader, who was found to have radicalized dozens of young men and recruited them to fight abroad, was sentenced to 12 years in prison. Most of those convicted were tried in absentia as they are believed to still be in Syria or Iraq, while several are presumed dead. To combat the potential foreign fighter threat, Belgium has employed a mix of security measures and prevention efforts. In early 2013, Belgium updated its criminal code to include several new terrorism-related offenses, which cover public incitement, recruitment, and providing or receiving terrorist training (in Belgium or abroad). While these measures do not specifically criminalize traveling to participate in foreign conflicts, Belgian officials assert that they may be used to prosecute foreign fighters. Experts note, however, that collecting evidence of such activities in conflict zones such as Syria and Iraq, or proving terrorist intent, may make such prosecutions difficult. A proposal in 2013 from the Belgian Interior Ministry to criminalize leaving Belgium to become a foreign fighter was rejected by the Belgian cabinet for several reasons, including fears that it would discourage families of potential fighters from reporting their concerns, and that it could be mistakenly construed as a sign of Belgian support for the Asad regime in Syria. Belgian authorities have sought to ensure strong coordination between law enforcement and intelligence services, both at the national level and with local levels. A Coordination Unit for Threat Assessment maintains a list of those who may have traveled or are known to have traveled to Syria or Iraq, as well as those who appear to harbor intentions to do so; this list is routinely shared with various federal, regional, and local authorities. The Coordination Unit also systematically investigates and assesses the potential threat posed by each known returning fighter. In cases lacking enough evidence for a criminal prosecution, such returning fighters are referred to local authorities for follow-up and reintegration efforts; they may also be subject to monitoring by the security services. Belgium has also devoted significant attention to prevention and counter-radicalization efforts. In April 2013, the Belgian government adopted a new counter-radicalization strategy aimed at improving knowledge about the radicalization process, promoting social measures to help blunt factors that may lead to radicalization, enhancing the resilience of vulnerable groups, and increasing awareness at the local level. A new anti-radicalization unit has been created within the Belgian Interior Ministry tasked with deterring individuals from becoming foreign fighters and supporting local strategies to counter radicalization. Prevention measures implemented by various municipalities throughout Belgium have included combining police work with community engagement, establishing mentoring programs for at-risk youth, and providing free counseling services for families of aspiring foreign fighters. In addition, Belgian authorities have been active in developing narratives to counter Islamist extremist propaganda and on working with Internet and social media companies to reduce radical content online. In the wake of the January attacks in Paris and the subsequent police raids in Belgium, press reports indicate that the Belgian government plans to pursue additional counterterrorism and counter-radicalization measures. These may include expanding the list of existing offenses for which it would be possible to strip dual nationals of their Belgian citizenship, providing authorities with the ability to take away identity documents (in addition to confiscating passports or other travel documents) to impede travel to Syria or Iraq, making it easier to freeze assets of suspected terrorists or their supporters, and enhancing efforts to tackle radicalization processes in penitentiary facilities. Belgian officials are also reportedly reconsidering a version of the proposal initially rejected in 2013 to criminalize traveling to a conflict zone. The Belgian government has also proposed an extra €300 million (roughly $348 million) for counterterrorism initiatives. Furthermore, Belgium has played a leadership role in seeking to promote a Europe-wide response to the potential dangers posed by foreign fighters. As discussed previously, under Belgium's initiative, the so-called "Group of Nine" EU member states most affected by the foreign fighter phenomenon began meeting regularly in 2013 to exchange information and promote greater Europe-wide cooperation. Belgian officials assert that many of the steps now being considered and undertaken at EU level were initially developed through the "Group of Nine." For at least a decade, France has viewed Al Qaeda and related Islamist terrorist organizations such as Al Qaeda in the Islamic Maghreb (AQIM) as the most pressing threat to French national security. Over the past year, French officials have also become increasingly concerned by the rise of the Islamic State terrorist organization (known in France as Daech after its Arabic acronym). Successive French governments have aggressively sought to combat Islamist terrorism, both through military operations in West Africa's Sahel region, the Middle East, and Afghanistan and by implementing stringent domestic counterterrorism policies. Despite these efforts, the threat appears to have intensified in recent years. Several deadly attacks on French and European soil and a growing number of French citizens training and fighting with terrorist organizations in the Middle East and North Africa have caused particular concern. France, which is home to Europe's largest Muslim population (an estimated 5 million-6 million, or about 8% of the total population), is reportedly the source of the largest number of European fighters in Syria and Iraq, most of whom are thought to be fighting with the Islamic State group. French authorities estimate that about 1,400 of the estimated 3,000 Europeans currently fighting with terrorist groups in those countries are French citizens and underscore that this number more than doubled in 2014. The French government has declared that these citizens' return to France and Europe represents "the biggest threat the country faces in the coming years." The killing of 17 people in three related terrorist attacks in Paris in early January considerably heightened French, European, and U.S. concerns about the threat of Islamist terrorism and returning fighters. On January 7, French-born Muslim brothers Chérif and Saïd Kouachi stormed the headquarters of French satirical magazine Charlie Hebdo and fatally shot 11 Hebdo employees and one police officer. In separate incidents on January 8 and 9, a French-Muslim friend of the Kouachi brothers, Amedy Coulibaly, shot and killed a policewoman and four individuals he had taken hostage in a kosher supermarket. All three suspects were killed in shoot-outs with police on January 9. A full investigation into the attacks is ongoing, but media reports indicate that at least one of the Kouachi brothers had spent time in Yemen cultivating relationships with members of Al Qaeda in the Arabian Pennisula (AQAP). In a video found after the attacks, Coulibaly declared his allegiance to the Islamic State, though the extent of his contact with the group remains unclear. All three perpetrators had been under state surveillance at various times prior to the attacks, and two of the three had spent time in French prisons. The Paris attacks followed other attacks in France and in Europe that had already raised concern about the threat posed by radicalized French Muslims who have received terrorist training and support abroad. In May 2014, French police arrested a French citizen of Algerian descent, Mehdi Nemmouche, on charges that he killed four people during an attack that month at the Jewish Museum in Brussels, Belgium. Nemmouche reportedly spent over a year with Islamist militants in Syria after being radicalized in the French prison system. The Nemmouche arrest came two years after another French citizen of Algerian descent, Mohamed Merah, killed seven people—three soldiers, a rabbi, and three Jewish children—in France's Toulouse region over an eight-day period. Merah also reportedly developed ties to radical Islamists while serving time in prison. The recent attacks and the growing number of combatants training abroad have challenged what has long been considered a highly effective French law enforcement and counterterrorism apparatus. French prosecutors are afforded broad powers to pursue terrorism cases and, over the past decade, have been further emboldened by a series of new anti-terrorism laws. Law enforcement officials also have more authority than most of their European counterparts to monitor and detain terrorism suspects. Nonetheless, the aforementioned attacks have exposed apparent shortcomings. French authorities have been criticized for an apparent inability to prevent individuals under state surveillance with known links to violent extremists from carrying out killings. The suspects in the Paris, Brussels, and Toulouse attacks had all been previously questioned and monitored by French authorities, but surveillance reportedly was lifted in each case. Some analysts speculate that surveillance on the Kouachi brothers was lifted in 2013 and 2014 as France increasingly shifted attention to citizens fighting with the Islamic State; the brothers were thought to have connections in Yemen and possibly to AQAP, but not the Islamic State. Other observers counter that it may be unrealistic to expect any government to effectively monitor every individual identified as a possible threat, noting, for example, that the Kouachi brothers, "were two inactive targets who had been quiet for a long time. They were giving nothing away." Over the past year, and particularly in the aftermath of the Paris attacks, the French government has sought to address these and other perceived shortfalls through a series of new counterterrorism measures. The initiatives are focused both on strengthening law enforcement and on preventing radicalization through social and education programs. In late 2014, the government adopted a new anti-terrorism law, which, among other things, broadened the authority to impose travel bans on individuals suspected of seeking terrorist training abroad, imposed strict penalties for inciting or expressing support for terrorism, and authorized the blocking of websites that encourage terrorism. The French government has moved aggressively to use these new authorities since the Paris attacks, including seizing passports of individuals suspected of planning to travel to Syria and arresting individuals for speech deemed supportive of terrorism. In February 2015, the French Interior Ministry announced that it expected to seize close to 50 passports from individuals suspected of planning terrorist-related travel to Iraq and Syria during the first part of the year. In March 2015, French officials announced that they were blocking five websites accused of promoting terrorism, using new authorities that eliminate a previous requirement for a judge to authorize such decisions. In late January 2015, the French government said it would commit €736 million (about $854 million) in new funding over the next three years to new counterterrorism initiatives, including hiring 2,500 new law enforcement personnel, improving information-sharing between intelligence and police officials, streamlining surveillance authorities, and launching new counter-radicalization programs. The new hires are to include 1,100 new positions in the domestic intelligence apparatus and close to 1,000 new positions in the Justice Ministry, including court officials, prison administration, and youth services. In addition, in March 2015, the government announced that it was proposing a new surveillance law to address the perceived shortcomings of a 1991 law enacted before the Internet had become a primary means of communication. The proposed law, expected to be approved by Parliament, would allow authorities to monitor the digital and mobile communications of anyone linked to an investigation of a terrorist suspect. Prior approval of a judge would not be required, and Internet service providers and phone companies would be legally obliged to comply with government requests for data. Beyond the domestic sphere, the French government has been a vocal proponent of proposals for an EU-wide Passenger Name Record system and for strengthening cooperation between law enforcement authorities in EU member states. France says that it will implement its own PNR system by the end of 2015, regardless of the outcome of the ongoing discussions on the EU PNR proposal. French officials have also at various times advocated measures to strengthen EU border controls. In addition, France has joined Germany and the UK in calling on U.S.-based technology companies to more aggressively remove content from their servers and websites deemed to promote or incite terrorism. A focal point of the French government's new counter-radicalization programs is to be the French prison system. According to some estimates, up to half of France's 68,000 inmates are Muslim. The suspects in the Paris, Brussels, and Toulouse attacks are all thought to have been radicalized while incarcerated. Among other measures, France has pledged to increase the number of Muslim chaplains in its prison system by one-third and to expand an existing program that separates groups of radicalized prisoners from the rest of the prison population in order to prevent recruitment efforts. Muslim advocates have long pointed to the relatively small number of Muslim chaplains in French prisons as one factor that may aid the radicalization process. They say that the French prison system has about 180 Muslim chaplains, compared to 700 Christian ones, with an estimated 80% of Muslim inmates never seeing a chaplain. Some analysts point out that while France has developed a far-reaching law enforcement apparatus to counter terrorism, it has had limited success improving the integration of Muslims into French society. Critics of French integration policy contend that to effectively prevent radicalization, the government must do more to reverse the significant socioeconomic disparities between "native" French citizens and those of North African and/or Muslim descent. In particular, they question the effectiveness of a long-standing French model of assimilation that prohibits granting special consideration or treatment to different ethnic or religious groups. They argue, for example, that many policies adopted in the name of France's secularist values, including restricting the wearing of head scarves and banning the full face veil, may serve to further alienate Muslims who already feel disenfranchised. Some critics could also argue that new laws against speech deemed sympathetic to terrorists unfairly target Muslims. They point out that in the wake of the Paris attacks, French leaders have vehemently defended the rights of Charlie Hebdo to publish cartoons deemed by many to be offensive and inflammatory, while at the same time aggressively prosecuting other forms of offensive speech. Since discovering that three of the September 11 hijackers had lived and plotted in Germany, successive German governments have worked hard to strengthen counterterrorism and anti-radicalization efforts. These efforts have intensified over the past year as officials have become increasingly concerned by the threat posed by German citizens fighting with rebel and terrorist groups in Syria and Iraq. As of April 2015, German authorities estimate that about 680 German fighters had traveled to Syria and Iraq since 2011, the majority of whom have now joined the Islamic State group. About one-third of these fighters reportedly have returned to Germany, and 85 have been killed in combat. German officials express particular concern about the apparently growing numbers of Germans joining extremist Salafist groups in Germany and going on to fight in Syria and Iraq. Between early 2014 and April 2015, estimates of the number of Germans fighting in the region more than doubled, rising from about 270 to 680. German intelligence officials report that fighters often come from Salafist circles that propagate a particularly radical form of Islam aimed at aligning all state and societal structures with the Koran. They estimate that as of April 2015, about 7,300 Germans were members of Salafist groups in Germany, compared to 3,800 in 2011. Germans fighting with the Islamic State reportedly have formed their own brigade within the terrorist organization. A significant number of these fighters are thought to have been previously affiliated with a German militant Islamist group named Millatu Ibrahim (Abraham's Religion). Millatu Ibrahim was banned by German authorities in May 2012 for its involvement in riots protesting the publication of caricatures of the prophet Mohammed in media outlets. Analysts believe that one of the group's German co-founders, a former hip-hop artist named Denis Cuspert (stage name Deso Dogg), is an "integral part of the [Islamic State] propaganda effort," including by overseeing the production of a variety of German language material. The German government takes a multifaceted approach to countering terrorism and violent extremism, including law enforcement measures and social and economic policies aimed at preventing radicalization. On the law enforcement side, the government has sought to strengthen existing laws that criminalize travel with intent to train with a terrorist organization, terrorist recruitment, and providing support to terrorist organizations. In December 2014, a German court for the first time sentenced an individual to a jail term for joining a militant group in Syria. Authorities have confiscated the passports of several German citizens suspected of planning "terrorist travel," and have also banned numerous religious organizations suspected of providing support to or recruiting for Islamist terrorists. Nonetheless, some analysts and policymakers have expressed concern about the difficulty of successfully prosecuting suspected terrorists under existing laws. They note, for example, the high burden of proof to establish terrorist intent behind travel to Syria and Iraq, and the difficulty of proving that individuals have been active with terrorist organizations after they return home. In January 2015, Berlin announced proposals to address perceived shortcomings in existing laws against "terror tourism" and to grant new authority to collect and save communication data from its citizens. Among other things, the newly proposed laws would allow authorities to confiscate identity cards as well as passports from suspected terrorists—residents can currently travel throughout Europe and to Turkey with identity cards, but without passports. The proposed new surveillance authorities could be particularly controversial given long-standing German concerns about privacy rights. In addition, while many law enforcement officials have welcomed the measures, some emphasize that additional resources, including highly qualified investigators, may be more important. They argue, for example, that they do not have the resources necessary to conduct the level of surveillance necessary to enforce existing laws. Law enforcement efforts have met with some success. Since 9/11, Germany has not experienced a major terrorist attack on the scale of those in France, Spain, or the UK. The first and thus far only deadly Islamist-motivated attack on German soil occurred in 2011, when a German resident from predominantly Muslim Kosovo killed two U.S. airmen and seriously wounded two others in a shooting at the Frankfurt airport. Over the past decade, authorities have broken up several terrorist cells they claim were plotting significant attacks on German soil. In 2010, three German citizens and a Turkish resident in Germany were convicted of plotting what German investigators say could have been one of the deadliest attacks in European postwar history. The group, all members of the Islamic Jihad Union (IJU), was arrested in 2007 as it prepared to carry out attacks on Ramstein Airbase and other U.S. military and diplomatic installations. In the weeks following the Paris attacks in early 2015, German police raided several properties linked to radical Islamist groups alleged to be planning terrorist attacks in Syria. The raids resulted in at least four arrests, including of two men suspected of having joined the Islamic State after traveling to Syria in 2013. The German government has also devoted significant resources to preventing radicalization, including through efforts to better integrate German Muslims who may feel alienated from broader society. An estimated 4 million Muslims live in Germany, making up roughly 5% of the general population; of which almost two-thirds are thought to have Turkish roots. Although the vast majority of Muslims living in Germany are seen to be relatively moderate in how religion affects their public conduct, support for more extremist views may be on the rise, especially among some younger Muslims. It is thought that some Muslim youth do not identify with Germany and are increasingly motivated by pan-Islamic notions of Muslim humiliation around the world, the plight of the Palestinians, and perceived U.S. subjugation of Arab countries. Despite advances in some areas, overall Muslim integration into German society has been minimal. Germans and Muslims often blame each other for this. Many "native" Germans see Muslims as refusing to accept German norms and values and as wanting to stay apart from the majority population. German attitudes toward Muslim communities, though rooted in differences in culture and values, also have been exacerbated by persistent social and economic problems facing the country as a whole. Many Muslims view German society as unwilling to fully accept people of different races, regardless of whether they assimilate or not. Some observers say that this reluctance could play into the hands of fundamentalists "by both defining German-ness in opposition to Islam and deepening the Turkish community's sense of being Muslim." Public debate over the role of Muslims in German society has increased over the past year, and especially in the wake of terrorist attacks in Paris and Copenhagen. Tensions have been catalyzed by weekly marches in the eastern city of Dresden organized by a new far-right, anti-Islam organization named PEGIDA (German acronym for Patriotic Europeans Against Islamization of the West). Between October 2014 and January 2015, the PEGIDA marches steadily grew in size, reaching a high of about 17,000 participants. After drawing sharp condemnation from across the political spectrum and spurring large counter-protests throughout Germany, the PEGIDA marches have since dwindled in size. However, the movement's emergence has exposed doubts about Islam's compatibility with the country's democratic values. German leaders have been particularly challenged to balance their desire to support and promote tolerance of Islam with their condemnation of violent Islamist extremism. The International Center for the Study of Radicalisation and Political Violence (ICSR) estimates that 50 to 100 Spanish citizens have joined jihadist groups fighting in Syria and Iraq. Additionally, however, Moroccan authorities have estimated that at least 1,200 Moroccan nationals with Spanish residency cards have joined the Islamic State group. About 70% of the over 1 million Muslims living in Spain have their origins in Morocco. At least 100 fighters from France and Morocco are thought to have transited through Spain in order to reach Turkey and travel on to Syria. Over the past two years, Spanish police have conducted raids to dismantle jihadist recruiting networks active in Ceuta and Melilla, Spanish enclaves located on the coast of Morocco, as well as in Madrid. In December 2014, a joint Spanish-Moroccan operation dismantled a network active in recruiting women to travel and join the Islamic State organization. Studies analyzing 20 individuals known to have traveled from Spain to join the conflict as of early 2014 reveal 11 Spanish citizens and nine Moroccan nationals living in Spain, most in their mid-20s or early 30s, and many married with children. The majority of these individuals came from Ceuta. The group included students, taxi drivers, unskilled workers, and unemployed individuals. One individual, Mouhannad Almallah Dabas, a naturalized Spaniard who was born in Syria, was connected to an Al Qaeda cell that operated in Spain from the mid-1990s to 2001 and was convicted in the 2004 Madrid train bombings, although his sentence was later overturned by the country's Supreme Court. Dabas was killed in Homs, Syria, in October 2013 while allegedly fighting for Jabhat al-Nusra. Most of the others had no previously known jihadist background, although several had criminal pasts, including drug charges. Many are thought to have been recruited and radicalized by experienced agents of a Spain-Morocco jihadi network whose Spanish-territory operations were dismantled by authorities between June and September 2013. Several individuals attended Attauba mosque in Ceuta, which has hosted radical imams in the past. At least three members of the group became suicide bombers in Syria. Spain has extensive experience in confronting domestic terrorism. The Basque separatist group ETA waged a violent campaign for over 40 years before declaring a permanent ceasefire in 2011. As a result of these experiences, Spain has a considerable body of counterterrorism legislation and entrenched procedures within its existing legal codes. Under the Spanish Penal Code, terrorist offenses are treated as an aggravated form of crime. Observers note, however, that this legislation was built largely around combatting organized groups such as ETA. The 2004 Madrid attacks marked a new type of threat, and Spain has sought to reform its penal code in order to adapt to more loosely organized cells, lone wolf actors, and recruitment or incitement activities. Legal reforms in 2010, for example, criminalized offenses such as recruitment or indoctrination, online incitement of terrorism, providing terrorist financing, and providing terrorism-related training. Additionally, following the Madrid attacks, the Spanish government sharply increased resources for national anti-terrorist agencies and sought to better integrate their work. Nevertheless, critics have expressed concern that the overall conviction rate for terrorism-related charges in Spain has remained relatively low. One Spanish newspaper reported in January 2015 that out of 571 arrests related to radical Islam since 2004, Spanish courts have convicted fewer than 100 people. Some observers assert that prosecutions have been hindered by strict evidence requirements, high standards of proof for intent and conspiracy, strong safeguards on civil liberties, and accusations of police misconduct. In relation to the foreign fighter issue, the high burden of proof has made it difficult to preemptively charge individuals with terrorism-related crimes before they were able to leave Spain. In September 2014, the Spanish government announced its intention to strengthen counterterrorism laws and police powers in response to the foreign fighter threat. The governing Popular Party (PP) subsequently proposed the addition of new amendments into a broader project to reform the penal code, including making it a criminal offense to receive terrorist training (past reforms criminalized providing training only) or to participate in an armed conflict abroad, and allowing the government to revoke the citizenship of those participating in terrorist activity. Additional proposals would allow for passport seizures, accelerated expulsion orders, reentry bans of identified extremists, and the introduction of streamlined search and capture warrants for police to arrest fighters attempting to travel to conflict zones. The government also indicated planned reforms to the regulation of evidence collection and standards for witness protection, in order to improve the success rate of terrorism-related prosecutions. Spain is working to introduce a national Passenger Name Record system for commercial air travel by the end of 2015. The terrorist attacks in Paris in early 2015 created a heightened sense of urgency for these efforts. In January 2015, the PP and the main opposition Socialist Party (PSOE) jointly re-drafted the proposals as a separate new counterterrorism bill. Rather than advancing the proposals piecemeal in the context of the wider penal code reform, this move combined the measures into a single piece of legislation submitted to the Spanish Parliament for fast-track approval and adopted on March 30, 2015. Human rights and civil liberties advocates have criticized the government's proposals, arguing that they create a vague and overly broad definition of terrorism that could infringe on the freedoms of expression and movement, the right to privacy, and the presumption of innocence. Among other objections, critics assert that the proposals outlaw planning to travel outside the country to train with a militant group, even if no such travel takes place, and make it illegal to express a statement on social media that could be perceived as inciting terrorism, even if not linked to a specific terrorist act. In January 2015, the Spanish government approved a Strategic National Plan to Fight Violent Radicalization, "a framework plan for the different public authorities to detect and act against potential outbreaks of radicalization, in a timely and coordinated fashion." Under the coordination of the Home Affairs Ministry, the plan establishes a new National Group to Combat Violent Radicalization that includes representatives from national government ministries, the intelligence community, provincial and city governments, and nongovernment institutions and associations. The aim is to create "the necessary structures and work plan to detect and intervene in pockets of potential radicalization ... with the aim of breaking up the chain of transmission of radicalization that makes individuals take the decision to become violent and, in the work-case scenario, become terrorists." Additional priorities of the initiative include generating counter-narratives against the spread of radical messages online and combating radicalization in prisons. The International Centre for the Study of Radicalisation and Political Violence (ICSR) and official British government sources estimate that 500 to 600 people have traveled from the UK to fight in Syria and Iraq. Other sources suggest that this figure represents a minimum estimate, with the actual number as high as 1,000 to 2,000. UK authorities have been actively concerned about this trend since 2011, but the issue has gained a higher profile with the appearance of identified or presumed British fighters in several Islamic State propaganda videos since mid-2014. British fighters in Syria have also reportedly carried out suicide bombings, and researchers have confirmed the deaths of 26 individuals who have traveled from the UK to fight. Given the difficulties of monitoring and verification, the actual total could be higher. Approximately 2.9 million Muslims live in the United Kingdom. About two-thirds of British Muslims have a South Asian background. Although the majority of Muslims in the UK are not involved in extremist activities, a fringe community exists that advocates radical Islamism and, in some cases, supports violent extremism. The UK government believes that up to 250 individuals who trained or fought in Syria or Iraq have already returned home to the UK. Given the potential for returning extremists to plot attacks on domestic targets, the UK's Joint Terrorism Analysis Centre raised the country's terror threat level from "substantial" to "severe" on August 29, 2014, indicating that authorities consider an attack to be highly likely. According to the ICSR, the broad profile for many of the British foreign fighters in Syria and Iraq is of a male in his 20s, of South Asian ethnic origin, with recent connections to higher education and links to individuals or groups who have international connections. Other analysts assert that while there is no single profile, a high proportion of British foreign fighters in Syria and Iraq have criminal pasts, with either a history of petty crime, previous incarceration for extremist Islamist behavior, or are hardened career criminals. Profile analysis of 23 UK fighters known to have been killed indicates that they were all second-generation immigrants from ethnic backgrounds, including Libyan, Palestinian, Eritrean, and Bangladeshi, with an average age of 23. Many had held relatively well-paying jobs and were enrolled in or had completed higher education, although several had significant criminal records and had spent time in prison. The UK's approach to addressing the foreign fighter threat contains three main elements. The first focuses on preventing suspects from traveling to or from the United Kingdom using powers to revoke passports, barring foreign nationals from reentry, and stripping dual nationals or naturalized citizens of their UK citizenship. The government has reportedly revoked the British citizenship of 27 people since 2010, the overwhelming majority due to terrorism-related activities, and has refused or cancelled the passports of 29 individuals planning to engage in terrorist activity abroad. According to Home Secretary Theresa May, as of November 2014, a total of 133 people had been excluded from the UK due to reasons of national security or the "public good," including 84 "hate preachers." The UK is currently the only EU member state that has implemented a national Passenger Name Record system, beginning development under an initiative launched in 2003. Although the system collects advanced passenger information for all commercial flights to the UK originating outside the EU, critics observe that it covers only about two-thirds of total air, rail, and maritime arrivals. Due to restrictions in some EU countries, for example, the system applies to about 70% of intra-EU flights to the UK, and advance data for private airplanes and boats remains difficult to collect. The second element to the UK's approach is managing suspected extremists already in the country. The Home Secretary has the power to impose terrorism prevention and investigation measures (formerly known as "control orders"), such as house arrest and restrictions on telephone and Internet use. Backed by an extensive set of counterterrorism legislation, UK security services and police also have a wide range of powers that can be used in efforts to prevent attacks and prosecute those planning them. Home Secretary May indicated in November 2014 that since 2010, 753 people have been arrested in the UK for terrorism-related offenses, 212 have been charged, and 148 successfully prosecuted. There are 138 individuals in the UK serving prison sentences for terrorism-related offenses, and 13 people have been extradited to face terrorism charges abroad. Third, the UK government's counterterrorism strategy includes a component called Prevent that seeks to combat the ideology of Islamist extremism, including by banning hate preachers and organizations that incite terrorism; attempting to counter radicalization and extremist recruitment in schools, universities, prisons , and mosques; and working with a network of organizations that offer support to those at risk. These efforts also include combating extremist material on the Internet. A Counter Terrorism Internet Referral Unit set up in 2010 has taken down over 65,000 unlawful terrorist-related websites, with over 70% of the unit's current caseload reportedly related to the Islamic State organization. In September 2014, Prime Minister David Cameron announced plans to further enhance the government's powers to counter the growing threat posed by foreign fighters. This initiative developed into the Counter-Terrorism and Security Act that was adopted in February 2015. The new act Broadens the powers of police and border officials to temporarily confiscate the passports of terrorism suspects for up to 30 days, with judicial review of the decision after two weeks. Currently, the Home Secretary must personally authorize the seizure of a passport. The bill also introduces new Temporary Exclusion Orders banning suspected terrorists with British passports from the country for two years, cancelling their passports, and placing them on "no fly lists." Individuals wishing to return may face prosecution or be forced to complete de-radicalization programs and may face two-year renewable orders restricting their movements, requiring them to check in regularly with the police, and notify authorities of contact with other extremists. Attempting to return in secret is defined as a new criminal offense carrying a five-year sentence. Amends the Terrorism Prevention and Investigation Measures Act 2011, reintroducing the power to relocate suspects within the UK and limit the distance they may travel. The bill increases the standard of proof for imposing a measure from "reasonable suspicion" to "balance of probabilities." Amends the Data Retention and Investigatory Powers Act 2014, requiring mobile phone and Internet service providers to retain data allowing relevant authorities to identify the individual or device that was using a particular Internet protocol (IP) address at a given time. Replaces existing "authority to carry" provisions for air, maritime, and rail carriers, requiring the advance provision of additional passenger, crew, and service information, including passenger credit card details. Puts the Prevent strategy on a statutory footing. Relevant institutions (e.g., prisons, universities, schools, and mosques) face a new legal duty to report extremism and develop policies to deal with radicals and extremist speakers. Makes it illegal for insurance companies to cover terrorist ransom payments. Creates a Privacy and Civil Liberties Board to assist the Independent Reviewer of Terrorism Legislation in monitoring the operation and impact of the UK's counterterrorism legislation. Human rights and civil liberties advocates have criticized aspects of the legislation. Some critics maintain that the enhanced powers to seize passports at the border could result in greater ethnic profiling. Others argue that Temporary Exclusion Orders amount to "dumping" citizens and "abdicating ... responsibilities to the international community." Critics additionally assert that the reintroduction of relocation powers under Terrorism Prevention and Investigation Measures are a form of "internal exile." The International Centre for the Study of Radicalisation and Political Violence (ICSR) estimates that 800 to 1,500 individuals have travelled from Russia to join groups involved in the conflict in Syria and Iraq. The majority of these fighters are thought to come from Chechnya and other parts of the North Caucasus, regions of Russia that have predominantly Muslim populations. Other sources estimate the number to be much higher, with as many as 2,500 Chechens and other North Caucasians fighting with the Islamic State group or Jabhat al-Nusra in Syria and Iraq. In recent months, numerous commanders of the proclaimed Caucasus Emirate have reportedly transferred their loyalties to the Islamic State organization. Analysts assert that many Chechen fighters tend to be relatively experienced and combat-ready, based on fighting Russia in a conflict that has been ongoing since the 1990s. Chechen fighters may therefore take on more leadership roles within extremist groups. One of the Islamic State's leading military commanders, for example, is Abu Omar al-Shishani ("Omar the Chechen"), who was born in Georgia to an ethnic Georgian Orthodox Christian father and an ethnic Chechen Muslim mother. Russian authorities have sought to use tight border controls in Chechnya and the North Caucasus to prevent travel to and from the conflict region. In regions such as Chechnya and Dagestan, there have reportedly been efforts by local authorities and media, as well as at mosques and schools, to discourage young men from travelling to Syria or Iraq to join armed groups. Russia has also used police operations to identify potential extremists and sought to prosecute individuals involved in terrorist activities. Russian legislation makes it a criminal offense to participate in an armed group abroad "whose aims are contrary to Russian interests" or to receive training "with the aim of carrying out terrorist activity." Some analysts have pointed out that the recent increase in tensions and mistrust between the United States and Russia over Ukraine has hindered possibilities for intelligence-sharing on the foreign fighter issue. The ICSR estimates that up to 650 individuals have traveled to the conflict from the countries of the Western Balkans (estimates are Albania, 90; Bosnia-Herzegovina, 330; Kosovo, 100 to 150; Macedonia, 12; Serbia, 50 to 70). Studies suggest that over 80% of fighters from the Western Balkans initially joined Jabhat al-Nusra, with a marked shift to the Islamic State group starting in 2013. The number of fighters from the region thought to have been killed in the conflict is approximately 40 to 50, and the number thought to have returned home is approximately 70 to 90. Data patterns for known foreign fighters from the Western Balkans appear to reveal several main clusters, with groups of individuals linked to isolated, radical communities in Bosnia or Serbia or to radical networks based around several informal mosques in Albania. Albania, Bosnia-Herzegovina, Kosovo, Macedonia, and Serbia all introduced foreign fighter-related changes to their criminal codes in 2014. Bosnia-Herzegovina, with the largest number of fighters from the region, notably closed a legal loophole with passage of a law criminalizing facilitation or participation in foreign fighting. In September 2014, Bosnian authorities reportedly arrested 16 individuals under the new law, which carries a sentence of up to 10 years in prison. Authorities in Serbia, Albania, and Kosovo also made a number of arrests in 2014 linked to foreign fighter facilitation or travel to Syria, with 55 individuals reportedly arrested in Kosovo and five charged in Serbia in October 2014 alone. The United States has extensive bilateral law enforcement and intelligence relationships with most European countries. France, Germany, and the United Kingdom are among the closest U.S. partners in this regard. U.S. police and intelligence services have been assisting their French counterparts with the investigation of the January 2015 attacks, and news reports have shed light on the steady U.S.-French exchange of information on the alleged perpetrators, their travel, and other suspected terrorists and foreign fighters. Since 2001, the United States and the European Union have also greatly expanded their law enforcement cooperation, especially against terrorism. U.S.-EU dialogue on police, judicial, and border control matters has increased substantially, and a number of U.S.-EU information-sharing agreements have been concluded over the years. In addition, U.S. and European policymakers have sought to cooperate on preventing radicalization and countering violent extremism. The United States has partnered with many European countries to share information and "best practices" on CVE measures, including social programs, counter-narrative initiatives, and civil society engagement efforts. In 2010, the United States and the EU convened an expert-level dialogue for the first time on preventing violent extremism. European governments and the EU have also worked closely with the United States in the 30-member multilateral Global Counterterrorism Forum (GCTF), founded in 2011. GCTF efforts have included mobilizing CVE resources and expertise, strengthening criminal justice and rule of law capacities, and enhancing international counterterrorism cooperation. Nevertheless, some challenges remain in promoting closer U.S.-European counterterrorism cooperation. Data privacy has long been a key sticking point. U.S. and European officials also continue to grapple with finding the appropriate balance between strengthening transportation and border security and facilitating legitimate transatlantic travel and commerce. Such issues have come to the forefront of U.S.-European discussions again amid the emerging foreign fighter threat. Some U.S. policymakers, including several Members of Congress, have expressed particular worries about European fighters in Syria and Iraq because the U.S. Visa Waiver Program permits short-term visa-free travel for citizens of most European countries (see "Issues for Congress" for more information). Recently, U.S. and European counterterrorism cooperation has focused heavily on ways to combat the foreign fighter phenomenon given increasing concerns that both European and American Muslims are being recruited to fight with Islamist groups in Syria and Iraq. In September 2014, the White House noted that U.S. officials from the Department of Justice and the Department of Homeland Security are "working closely" with European counterparts on "a wide range of measures focused on enhancing counter-radicalization, border security, aviation security, and information sharing" to address potential threats posed by foreign fighters. On January 11, 2015, in the aftermath of the Paris attacks, U.S. Attorney General Eric Holder attended an emergency meeting of European and North American interior ministers to discuss terrorist threats and foreign fighters. High-ranking European officials were also key participants in the February 2015 CVE conference hosted by the United States in Washington, DC. Given the EU's largely open internal borders, U.S. officials have been encouraging the EU to move forward with approving and implementing its own system for collecting airline Passenger Name Record data to help counter the potential threat from returning fighters. U.S. policymakers have also urged the EU to make greater use of the Schengen Information System. U.S. officials and analysts contend that the foreign fighter phenomenon underscores the importance of close bilateral law enforcement ties with European allies and existing U.S.-EU information-sharing arrangements. These include the following: two agreements that allow U.S. law enforcement authorities and Europol to share both strategic information (such as threat tips, crime patterns, and risk assessments) and personal information (names, addresses, phone numbers, and criminal records about suspects in crimes covered by Europol's mandate); the U.S.-EU PNR agreement, which permits airlines flying to and from Europe to share airline passenger data with U.S. authorities; and the U.S.-EU Terrorist Finance Tracking Program (TFTP) agreement (also known as the U.S.-EU SWIFT accord), which allows U.S. authorities access to financial data held by a Belgium-based consortium of international banks. Despite the common commitment on both sides of the Atlantic to bolster efforts against the potential foreign fighter threat, some issues could pose hurdles to greater U.S.-European cooperation. U.S.-European differences on data privacy continue to make information-sharing accords such as SWIFT and PNR controversial in Europe. The EU considers the privacy of personal data a basic right, and EU law prohibits the transfer of such data to countries where legal protections are not deemed "adequate." Many European privacy advocates and some EU policymakers (especially in the European Parliament) have long voiced objections to the SWIFT and PNR agreements due to fears that the United States cannot guarantee a sufficient level of protection for European citizens' personal information. Both the SWIFT and PNR accords will be up for renewal in the near future (SWIFT in mid-2015 and PNR in 2019) and have come under renewed scrutiny following the unauthorized disclosures of classified U.S. surveillance activities since June 2013. Some analysts are concerned that future iterations of the agreements between the United States and the EU may not be able to secure the necessary European Parliament approval. Others suggest that the potential threat posed by returning Islamist fighters may moderate any possible opposition to renewing these accords. Other differences in perspective and policy approaches also exist. For example, U.S. authorities have reportedly questioned plans by some European governments to revoke passports of citizens who have gone to fight in Syria or Iraq to prevent them from returning home. Some U.S. officials suggest it may be more useful to question and monitor such returning fighters to enhance intelligence collection, both about domestic terrorist or extremist networks and about the situation on the ground in the conflict zone. In addition, varying U.S. and European views and laws on freedom of speech, including online, could pose difficulties for U.S.-European cooperation in countering radicalization and extremist propaganda. In the past, for example, U.S.-European frictions have surfaced over racist and anti-Semitic material on U.S. websites—which would be illegal if hosted on Internet servers located in European countries such as Germany or France—but which are largely protected in the United States by the right to free speech enshrined in the First Amendment of the U.S. Constitution. Similarly, many European officials have expressed concerns about terrorist and extremist content online, the vast majority of which is hosted on U.S. servers. Following the attacks in Paris in January 2015, France, Germany, and the UK called on Internet and social media companies to begin preemptively removing terrorist content from their sites. U.S. technology firms largely oppose European demands for preemptive filtering because they worry about becoming the arbiters of acceptable discussion online; they also question to what extent they must comply with local laws limiting online speech that may not violate U.S. laws. U.S. industry leaders assert that they do remove content that incites terrorism or recruits people to join terrorist organizations, but contend that determining where to draw the line can be a difficult issue (especially with respect to sarcasm or hyperbole), and oppose a broad legal overhaul as unworkable. Furthermore, U.S. technology companies suggest that complying with European calls for preemptive filtering could have negative implications for global Internet freedom, setting a bad precedent with respect to countries such as Turkey, Russia, or China. Meanwhile, some U.S. and European law enforcement officials worry that automatically closing down websites with terrorist content could be counterproductive because such sites often serve as useful intelligence and monitoring tools. Several congressional hearings in the 113 th and 114 th Congresses have focused on or addressed the foreign fighter phenomenon, especially as related to Europe. Senate Homeland Security and Governmental Affairs Committee, "Cybersecurity, Terrorism, and Beyond: Addressing Evolving Threats to the Homeland," 113 th Congress, 2 nd Session, September 10, 2014; House Homeland Security Committee, Subcommittee on Border and Maritime Security, "One Flight Away: An Examination of the Threat Posed by ISIS Terrorists with Western Passports," 113 th Congress, 2 nd Session, September 10, 2014; House Homeland Security Committee, "Worldwide Threats to the Homeland," 113 th Congress, 2 nd Session, September 17, 2014; House Foreign Affairs Committee, Subcommittee on Europe, Eurasia, and Emerging Threats, "Islamist Foreign Fighters Returning Home and the Threat to Europe," 113 th Congress, 2 nd Session, September 19, 2014; House Foreign Affairs Committee, Joint Hearing of the Subcommittee on Terrorism, Nonproliferation and Trade, and the Subcommittee on the Middle East and North Africa, "ISIS and the Threat from Foreign Fighters," 113 th Congress, 2 nd Session, December 2, 2014; House Homeland Security Committee, "Countering Violent Islamist Extremism: The Urgent Threat of Foreign Fighters and Homegrown Terror," 114 th Congress, 1 st Session, February 11, 2015; Senate Homeland Security and Governmental Affairs Committee, "Visa Waiver Program: Implications for U.S. National Security," 114 th Congress, 1 st Session, March 12, 2015; House Homeland Security Committee, Subcommittee on Border and Maritime Security, "Combating Terrorist Travel: Does the Visa Waiver Program Keep Our Nation Safe?" 114 th Congress, 1 st Session, March 17, 2015; House Homeland Security Committee, "A Global Battleground: The Fight Against Islamist Extremism at Home and Abroad," 114 th Congress, 1 st Session, March 24, 2015. In many of these hearings, the U.S. Visa Waiver Program figured prominently given that a number of participating countries in Europe have sizeable foreign fighter contingents in Syria and Iraq. As discussed previously, the VWP permits short term visa-free travel (up to 90 days) for business or pleasure to the United States from 38 countries, most of which are in Europe. Congressional concerns about the ability of terrorists to enter the United States under the VWP are not new. Following the September 11, 2001, attacks and the realization that terrorists with European citizenship had traveled to the United States under the VWP (including the "20 th " September 11 hijacker, Zacarias Moussaoui, and airplane "shoe bomber" Richard Reid), Congress sought to strengthen the program's security components in legislation, such as the Enhanced Border Security and Visa Reform Act of 2002 ( P.L. 107-173 ) and the Implementing Recommendations of the 9/11 Commission Act of 2007 ( P.L. 110-53 ). Among other provisions, P.L. 110-53 called on participating VWP countries to meet certain security and passport standards and to sign on to a number of information-sharing agreements. P.L. 110-53 also required visitors entering the United States under the VWP to submit biographical information to U.S. authorities through a new web-based Electronic System for Travel Authorization (ESTA) at least two days before traveling. ESTA became operational in 2009. ESTA checks the biographical information submitted against relevant law enforcement and security databases; those individuals not approved under ESTA must obtain a U.S. visa. Prior to ESTA's implementation, the first time an individual traveling to the United States under the VWP was screened was at the port of departure; information submitted for ESTA is largely the same as that required by the previous I-94W form that individuals arriving under the VWP were required to complete en route to the United States. Amid growing concerns about terrorist threats emanating from the Syria-Iraq region, including the increasing numbers of foreign fighters, several pieces of legislation on the VWP were introduced in the 113 th Congress. Some proposed measures largely aimed to enhance the security of the VWP further (see H.R. 5470 , introduced September 15, 2014 by Representative Candice Miller, and S. 2869 , introduced September 23, 2014, by Senator Dan Coats). Others would have temporarily suspended the VWP or the participation of certain countries (see H.R. 5434 , introduced September 10, 2014, by Representative Doug Collins; and H.R. 5594 , introduced September 18, 2014, by Representative Tulsi Gabbard). At the start of the 114 th Congress, Representative Candice Miller reintroduced legislation to strengthen the VWP's security elements; it would also specify that the Department of Homeland Security can suspend a country's participation in the VWP should the country fail to provide the United States with pertinent traveler information related to security concerns (see H.R. 158 , the Visa Waiver Program Improvement Act of 2015, introduced January 6, 2015). Similarly, Senator Dan Coats has reintroduced legislation that, among other counterterrorism provisions, aims to improve the VWP's existing security controls (see S. 542 , the Counterterrorism Border Security Enhancement Act, introduced February 24, 2015). Regarding the VWP, S. 542 would expand pre-travel clearance procedures and increase information-sharing requirements for VWP participating countries; S. 542 would also specify that DHS may suspend a country from the VWP for not fully cooperating with such information-sharing requirements. The terrorist attacks in Paris and Copenhagen in early 2015 have prompted even more intense congressional scrutiny of the VWP. While some Members of Congress continue to express reservations about the program on security grounds, many recognize its importance in facilitating international trade and tourism of considerable economic significance for the United States. Others note the resource difficulties that the U.S. Department of State would face if the VWP was terminated. In FY2013, about 20 million people arrived in the United States under the VWP, representing more than one-third of all temporary visitors, and spent almost $80 billion while traveling to and within the United States. The Obama Administration continues to support the VWP as a key facilitator of transatlantic commerce and tourism and rejects calls to suspend it because of the potential foreign fighter threat. U.S. officials point out that ESTA's introduction has greatly strengthened the VWP's security controls over the last few years and that the program's information-sharing provisions with participating countries help to enhance U.S. intelligence about known and suspected terrorists and other criminals. In November 2014, the U.S. Department of Homeland Security announced that VWP travelers would be required to submit more biographic information through ESTA to help address growing security concerns about foreign fighters. U.S. officials contend that the additional ESTA requirements will enable more accurate and comprehensive screening of VWP visitors, while preserving legitimate trade and travel. In addition to voicing concerns about the VWP, some Members of Congress have questioned whether current European counterterrorism laws are equipped to combat the emerging foreign fighter threat. As discussed earlier, while some European countries already have laws in place that criminalize traveling abroad for terrorist purposes or the facilitation of such travel, others are in the process of considering or enacting such legislation. The EU may also amend its common definition of terrorism to make so-called "jihadi travel" and other related foreign fighter activities (such as receiving terrorist training) criminal offenses throughout the EU, both to take into account the requirements of UNSCR 2178 and to avoid prosecution gaps among member states. Administration officials assert that the United States is continuing to encourage all partners, including in Europe, to meet their obligations under UNSCR 2178. The United States would likely welcome an EU decision to update its common terrorism definition. However, many experts note that efforts to criminalize foreign fighter-related offenses could be controversial in some European countries seeking to balance security concerns with integration and rehabilitation imperatives. Meanwhile, reaching agreement at EU level on harmonizing member state laws on "jihadi travel" may face hurdles given differences in member states' legal systems, and lag times between when an agreement is reached by EU officials in Brussels and when it is implemented or enforced at the national level. In the wake of the Paris and Copenhagen attacks, several Members of Congress have also noted concerns about the extent and robustness of European information-sharing, both among European countries and with the United States. Many Members of Congress have expressed support for the EU-wide proposal on airline Passenger Name Record data as a way to help improve European capabilities to track potential foreign fighters. Congressional support has been consistently strong for the U.S.-EU PNR accord and the U.S.-EU SWIFT agreement as vital tools in the fight against terrorism. U.S. border control measures and visa policy may continue to be salient issues for Congress as the United States seeks to address the potential foreign fighter threat. Congressional decisions related to intelligence-gathering reforms and data privacy and protection issues may have implications for U.S.-European counterterrorism cooperation and the future of U.S.-EU information-sharing agreements in the years ahead. Members of Congress may be able to help shape European views and responses to the foreign fighter phenomenon through ongoing contacts with European lawmakers in national parliaments and in the European Parliament. Appendix A. Membership in the European Union, Schengen Area, and the U.S. Visa Waiver Program The following chart details participation of European countries in the 28-member European Union, the Schengen area of free movement, and the U.S. Visa Waiver Program (VWP). * Monaco, San Marino, and Vatican City are considered de facto members of the Schengen free movement area; they do not have border controls with the Schengen countries that surround them, but they are not official Schengen members because they have not signed the Schengen Agreement. Appendix B. Foreign Fighter Recruitment Patterns The dynamics of the Syrian conflict are such that the predominantly Sunni Muslim insurgents' requests for material support often make reference to Islamic religious injunctions to defend co-religionists. Such requests appear to have strong appeal in some Muslim communities around the world. Nevertheless, one also could argue that the power of these requests to convince individuals to become foreign fighters may be relatively limited, given that while foreign fighter flows to Syria have been large relative to similar flows to other conflicts in the past, these flows are relatively small when considered as a proportion of the large global Sunni Muslim population (which may exceed one billion people). Groups or individuals sympathetic to Syrian insurgents also have other means of providing support, including political advocacy and financial donations. Imbalances in the relative flow of fighters to Syria from particular countries or communities may suggest important differences in underlying social and political conditions in those areas or differences in the approaches taken by domestic authorities to prevent foreign fighter recruitment and/or restrict foreign fighter travel. In August 2014, the Islamic State organization issued a lengthy appeal to potential foreign recruits in its English-language web magazine (see Figure B-1 ). The appeal described travel to Iraq and Syria by foreign recruits in support of the Islamic State as analogous to the hijrah , a centerpiece of Islam's foundational story in which the prophet Mohammed and his earliest supporters fled persecution in Mecca for the relative safety of Yathrib (Medina) and later used Yathrib as a base for their subsequent military campaign against their detractors in the Arabian Peninsula. Other Salafist-Jihadist groups have used similar analogies in other contexts as a means of associating their appeals for military and financial support with religious and historical imagery intimately familiar to many Muslims. In the words of the Islamic State's appeal: Every Muslim professional who delayed his jihad in the past …should now make his number one priority to repent and answer the call to hijrah, especially after the establishment of the Khilafah [caliphate, announced by the Islamic State in June 2014]. This Khilafah is more in need than ever before for experts, professionals, and specialists, who can help contribute in strengthening its structure and tending to the needs of their Muslim brothers. … So abandoning hijrah–the path to jihad–is a dangerous matter. In effect, one is thereby deserting jihad and willingly accepting his tragic condition of being a hypocritical spectator. The Islamic State organization also warns prospective recruits of potentially difficult conditions and advises individuals to "keep in mind that the Khil a fah is a state whose inhabitants and soldiers are human beings. They are not infallible angels. You may see things that need improvement and that are being improved." In January 2015, Islamic State spokesman Abu Mohammed al Adnani reiterated his call for supporters to join the group's ranks and to carry out attacks in their home countries. In March, the group's English-language magazine featured a lengthy article extolling the virtues of male and female foreign recruits, and provided imagery of a young traveler in a Western airport en route to "the land of Islam" (see Figure B-2 ).

Summary: The rising number of U.S. and European citizens traveling to fight with rebel and terrorist groups in Syria and Iraq has emerged as a growing concern for U.S. and European leaders, including Members of Congress. Several deadly terrorist attacks in Europe over the past year—including the killing of 17 people in Paris in January 2015—have heightened the perception that these individuals could pose a serious security threat. Increasingly, terrorist suspects in Europe appear to have spent time with groups fighting in the Middle East, especially with the Islamic State organization (also known as ISIL or ISIS). Others, like the gunman who murdered two individuals in Copenhagen in February 2015, seem to have been inspired by Islamist extremist propaganda. U.S. intelligence suggests that more than 20,000 foreign fighters have traveled to the Syria-Iraq region, including at least 3,400 Westerners, since 2011. The vast majority of Western fighters are thought to be from Europe, although roughly 150 Americans have traveled or attempted to travel to Syria. U.S. authorities estimate that a handful of Americans have died in the conflict; they also assert that military operations against the Islamic State group since August 2014 have killed thousands of fighters, including an unknown number of foreigners. European governments have employed a mix of security measures and prevention efforts to address the potential foreign fighter threat. These have included increasing surveillance; prohibiting travel; countering terrorist recruitment and incitement to terrorism via the Internet and social media; and strengthening counter-radicalization programs. Steps are also being taken by the 28-member European Union (EU) to better combat the possible threat given the bloc's largely open internal borders (which permit individuals to travel without passport checks among most European countries). EU leaders have emphasized the need to enhance information-sharing among national and EU authorities, strengthen external border controls, and improve existing counter-radicalization efforts, particularly online. Nevertheless, European countries and the EU face a range of challenges in stemming the flow of fighters to Syria and Iraq and keeping track of those who go and return. Prosecuting such individuals is difficult in many European countries because most existing laws require a high level of proof that a suspect has actually engaged in terrorism abroad or has returned to commit a terrorist act. Due to ongoing resource constraints, even those governments with far-reaching legal authority to detain terrorist suspects have found it difficult to identify and monitor a growing number of potential assailants. Furthermore, implementation of several EU-wide measures under discussion could be slowed by national sovereignty concerns, long-standing law enforcement barriers to sharing sensitive information, and strong EU data privacy and protection rights. U.S. officials and analysts contend that the potential foreign fighter threat underscores the importance of close law enforcement ties with key European allies and existing U.S.-EU information-sharing arrangements, including those related to tracking terrorist financing and sharing airline passenger data. Some U.S. policymakers, including several Members of Congress, have expressed particular worries about European fighters in Syria and Iraq because the U.S. Visa Waiver Program (VWP) permits short-term visa-free travel to the United States for citizens of most European countries. At the same time, many point out that the VWP's existing security controls require VWP travelers to provide advanced biographic information to U.S. authorities and may help limit travel by known violent extremists. In the 113th Congress, several pieces of legislation were introduced on the VWP, ranging from proposals to limit or suspend the program to those that sought to strengthen the security of the VWP further. In the 114th Congress, two proposals—H.R. 158 and S. 542—largely aim to enhance the VWP's security components to better guard against potential terrorist threats. For additional information, see CRS Report RS22030, U.S.-EU Cooperation Against Terrorism, by [author name scrubbed], and CRS Report RL32221, Visa Waiver Program, by [author name scrubbed].