As the so-called Islamic State (ISIS) continues to lose territory, resources, and personnel, there is widespread concern about how to manage the outflow of people from countries where they are active. The evolving and contested relationship between migration, terrorism, and violent extremism animates electorates, governments, and international organizations. For many governments and communities, this requires a careful balance between the preservation of security and an effective humanitarian response.
Mobility is at the heart of current debates on terrorism. Since 2014, the international community has focused on the challenges posed by foreign terrorist fighters (FTFs) and their supporters. This was reflected in Security Council resolution 2178 in 2014 and subsequent work undertaken by the Council’s Counter-Terrorism Committee. As attention increasingly shifts to returning and relocating FTFs, many governments are focusing on the question of whether terrorist groups will utilize these population flows to mobilize operatives and resources, or whether vulnerable individuals within migrant groups will be radicalized or recruited.
The starting point is to acknowledge that migrants who are being radicalized or, indeed, participating in terrorist attacks, constitute a minute percentage of all migrants globally. Almost a quarter of a billion people are living outside of the country in which they were born. Within this broader migrant group, there are approximately 22.5 million refugees, and 40 million internally displaced persons. However, much of the public discourse around this topic is intensely polarised. On the one hand, the growth of populist rhetoric has led to increasingly restrictive migration policies that may prove counter-productive and actually increase the risk of radicalization. On the other hand, acknowledging that public discourse tends to exaggerate the threat posed by migrant communities should not mean ignoring potential risks.
First, while there is no single “pathway to radicalisation,” many of the associated risk factors tend to be present in refugee or other migrant communities: isolation and limited opportunities for social and economic development; limited interaction with local communities; and few educational opportunities. As recent UNDP research highlighted, real or perceived grievances against the state, which can drive migration, can also foster radicalization.
Second, recent years have seen migrants implicated in a number of terrorist incidents. Two of the perpetrators of the Paris attacks in November 2015 reached Europe by falsely claiming to be Syrian nationals seeking asylum. Between July 2016 and October 2017, persons who had sought asylum were involved in nine terrorist attacks or foiled attacks, across five countries. Reports persist that certain refugee camps are being infiltrated by terrorist organizations.
Third, some countries have raised concerns that their diasporas—who for the reasons outlined above may be at greater risk of radicalization—are in turn playing a radicalizing role or even financing terrorist activities in their country of origin.
These are manifestations of diverse and complex phenomena. Determining appropriate policy responses is further complicated by a lack of data regarding, for example: how often states screen migrants against INTERPOL watch-lists upon arrival; the frequency with which host states initiate prosecutions rather than deportations when migrants are suspected of involvement in terrorist activity; and the extent to which migrant groups are incorporated into programs to prevent or counter violent extremism (P/CVE).
What can be said with some confidence is that responses must be comprehensive, combining the more “traditional” counter-terrorism mechanisms with preventive measures to build communities’ resilience against radicalization. It will remain important for states to strengthen their border management and law enforcement mechanisms, to identify at the earliest possible stage any potential links to terrorism which a migrant may have and, thereafter, ensure that any migrants who have been involved in terrorism-related activities are brought to justice. As highlighted in UN counterterrorism assessments, challenges in this area include: lengthy, porous borders; a lack of adequate infrastructure, equipment, or personnel at official crossing points; and difficulties in accessing and utilizing digital evidence.
In itself, strengthening these traditional mechanisms will not suffice. While states have expanded their counterterrorism toolkit over the past decade, P/CVE programming has only been undertaken within a select number of countries. Moreover, to date there appears to have been limited outreach to migrant and refugee communities and, in particular, minimal attention to differential drivers of radicalization among women and girls in mobilized populations, or their vulnerabilities to recruitment or exploitation. We need to know more about what has been attempted so far, what has worked, and what has not.
Discussions during the recent opening of the 72nd session of the United Nations General Assembly may trigger renewed efforts to understand and address these complex phenomena. It is hoped that these will lead to responses that take into account the diversity, vulnerabilities, and the positive potential of migrant communities. However, inadequate or reflexive responses, based on limited data, will likely shrink the space for thoughtful, informed policy-making in this area yet further.
David McKeever is a Legal Officer in the Counter-Terrorism Committee Executive Directorate and Naureen Chowdhury Fink is a Gender Adviser, CTED.
The views expressed here are solely those of the authors, and do not necessarily reflect those of the United Nations.
 UN General Assembly, Report of the UN Special Rapporteur on the protection of human rights while countering terrorism, A/71/384, ¶ 53 (13 September 2016), https://undocs.org/A/71/384.
 UNDP, Journey to Extremism in Africa: Drivers, Incentives and the Tipping Point for Recruitment, 2017, http://journey-to-extremism.undp.org/content/downloads/UNDP-JourneyToExtremism-report-2017-english.pdf, 5.
 Alex P. Schmid, Links between Terrorism and Migration: An Exploration, May 2016, https://www.icct.nl/wp-content/uploads/2016/05/Alex-P.-Schmid-Links-between-Terrorism-and-Migration-1.pdf, 32–36.
 EUROPOL, Terrorism Situation and Trend Report 2017, https://www.europol.europa.eu/sites/default/files/documents/tesat2017_0.pdf, 41; Schmid, 38–39.
 UN Security Council, Letter to the President of the Security Council concerning terrorism, S/2016/49, ¶ 72, 94, 113, 133–35, 155, 171, 194–95, 229, 254, 324 (20 January 2016), http://www.securitycouncilreport.org/atf/cf/%7B65BFCF9B-6D27-4E9C-8CD3-CF6E4FF96FF9%7D/s_2016_49.pdf; UN Security Council, Report of the Secretary-General on the threat posed by ISIL, S/2017/97, ¶ 35–36 (2 February 2017), https://documents-dds-ny.un.org/doc/UNDOC/GEN/N17/024/61/PDF/N1702461.pdf?OpenElement; UN Security Council, Letter to the President of the Security Council concerning terrorism, S/2015/975, ¶ 32 (29 December 2015), http://www.un.org/en/sc/ctc/docs/2015/N1545987_EN.pdf.