The Islamic State group has mobilized tens of thousands of individuals from over 120 countries to fight in Iraq and Syria on behalf of the organization.1 Although the scope and scale of the (mostly) Islamic State-inspired migration is unprecedented, the foreign fighter phenomenon has shaped military conflicts in recent history. As the Islamic State continues to shrink, and sheds fighters who joined the battle from abroad, lessons from previous conflicts featuring foreign fighters may be illustrative.
The “anti-Soviet Jihad” in Afghanistan in the 1980s was the first modern conflict to see high levels of foreign fighter participation. From that conflict, a global militant community established the funding networks, credibility, and battlefield proficiency operationalized in Bosnia and Chechnya a decade later.
These conflicts follow similar patterns: conflict-induced humanitarian crises eventually precipitate supranational struggles drawing worldwide volunteers. After September 11, 2001, subsequent foreign fighter mobilizations evolve in how fighters migrate, fight, and communicate, but maintain the basic commonalities that shaped the first conflicts. The personal networks built in Afghanistan strengthened in Bosnia and Chechnya and were critical to shaping the conflicts in Iraq and Syria. Returning fighters from previous conflicts moved on to found many of the terror networks that gave rise to current jihadi-salafi organizations such as al Qaeda and the Islamic State.
Conflict-induced humanitarian crises eventually precipitate supranational struggles drawing worldwide volunteers.
Despite differences in space and time, common themes link each successive jihad. Each conflict was considered a defensive war on behalf of a local Muslim population, which enabled international supporters (both donors and fighters) to frame participation in the conflict as a religious duty. These conflicts were further linked by a common group of fighters who gained credibility and combat experience ultimately culminating in improved military effectiveness. As technology evolved, so too did the foreign fighters, and each conflict pioneered new approaches to waging “jihad through the media.” 2 Media outreach began with Afghanistan in the 1980s with flyers and newsletters for propaganda purposes, while today’s international militants broadcast their battles using video cameras and curated social media strategies. The fighters’ force-multiplying potential and military experience allowed them to change the nature of conflicts from national to supranational by situating local grievances within a pan-Islamic jihadist narrative. 3
1. Significant discrepancies in foreign fighter numbers result from the complexity of counting and tracking the flow of fighters into Syria, Iraq, and Libya. Intelligence and law enforcement agencies, the United Nations, and other entities monitoring foreign fighters are unable to provide wholly accurate information on what was believed to be 38,500 fighters from 120 nations by the time foreign fighter flows began to slow in 2016. “Remarks by Lisa O. Monaco at the Intelligence Studies Project at the University of Texas-Austin,” Lawfare, March 30, 2016, https://www.lawfareblog.com/lisa-monaco-speech-university-texas.
2. Cerwyn Moore and Paul Tumelty, “Foreign Fighters and the Case of Chechnya: A Critical Assessment,” Studies in Conflict & Terrorism 31, no. 5 (April 11, 2008): 417.
3. Thomas Hegghammer, “The Rise of Muslim Foreign Fighters: Islam and the Globalization of Jihad,” International Security 35, no. 3 (Winter 2010): 56.
4. Ibid., 85.
5. A network of Islamic charities based in the Hijaz region of Saudi Arabia was established by the Saudis in the 1980s to fund the Afghan mujahedeen. The elaborate network of donors, charities, and sponsors has since become a pipeline for terrorist group financing in conflicts from Chechnya to Palestine. (Juan Zarate, Treasury’s War: The Unleashing of a New Era of Financial Warfare (New York: Public Affairs, 2013), 67–69).
6. Hegghammer, “The Rise of Muslim Foreign Fighters,” 86.
7. Edwin Bakker and Jeanine de Roy van Zuijdewijn, “Returning Western Foreign Fighters: The Case of Afghanistan, Bosnia and Somalia,” ICCT Background Note, International Centre for Counter-Terrorism (ICCT), The Hague, 2014.
8. Hegghammer, “The Rise of Muslim Foreign Fighters,” 86.
9. Sheikh Abdullah Nassah al Waan to Sheikh Abdullah Azzam, “Defense of the Muslim Lands,” accessed March 1, 2017, https://archive.org/stream/Defense_of_the_Muslim_Lands/Defense_of_the_Muslim_Lands_djvu.txt.
10. “Shatter-zone” refers to border areas between major powers, in this case in Afghanistan, in which conflict frequently erupts as major powers compete for influence. (R. McMaster, “Harbingers of Future War: Implications for the Army with Lieutenant General H.R. McMaster,” May 4, 2016, https://www.csis.org/analysis/harbingers-future-war-implications-army-lieutenant-general-hr-mcmaster/?block1.)
12. Brian Glyn Williams, “On the Trail of the ‘Lions of Islam’: Foreign Fighters in Afghanistan and Pakistan, 1980–2010,” Orbis 55, no. 2 (2011): 216–39.
13. The term mujahedeen refers to those who participate in a struggle or fight against the enemies of Islam. The term popularly was used to refer to the guerrilla forces in the Soviet-Afghan war, but can be used to refer to those fighting in the name of Islam in any conflict.
14. Williams, “On the Trail of the ‘Lions of Islam,’” 219; Hegghammer, “The Rise of Muslim Foreign Fighters,” 61.
15. West Point’s CTC Sentinel estimated the number of foreign fighters in Afghanistan at 10,000. Mohammed M. Hafez, “Jihad after Iraq: Lessons from the Arab Afghans Phenomenon,” CTC Sentinel 1, no. 4 (March 2008): 1–4, https://www.ctc.usma.edu/v2/wp-content/uploads/2010/07/CTCSentinel-Vol1Iss4.pdf. Peter Neumann and Thomas Hegghammer both estimate the number of foreign fighters in Afghanistan at 20,000. Peter Neumann, “Foreign Fighter Total in Syria/Iraq Now Exceeds 20,000; Surpasses Afghanistan Conflict in the 1980s,” International Centre for the Study of Radicalisation and Political Violence, January 26, 2015, https://icsr.info/2015/01/foreign-fighter-total-syriairaq-now-exceeds-20000-surpasses-afghanistan-conflict-1980s/; Hegghammer, “The Rise of Muslim Foreign Fighters,” 53–94. However, Ahmed Rashid estimated that the number of fighters in Afghanistan was closer to 35,000. Ahmed Rashid, Taliban: Militant Islam, Oil and Fundamentalism in Central Asia, Second Edition, 2nd ed. (New Haven, CT: Yale University Press, 2010): 129.
16. Hegghammer, “The Rise of Muslim Foreign Fighters,” 62.
17. The term “Afghan Arabs” refers to the primarily Arab mujahedeen who traveled to Afghanistan to help their fellow Muslims fight against the Soviets.
18. Evan Kohlmann, Al-Qaida’s Jihad in Europe: The Afghan-Bosnian Network (New York: Berg, 2004), 9.
19. Azzam was killed by an IED in Peshawar several months later. It remains unclear who was responsible for his assassination, but suspects include Ayman al Zawahiri, the Iranian Ministry of Intelligence, and Jordanian intelligence in coordination with the CIA. See also Williams, “On the Trail of the ‘Lions of Islam,’” 219.
20. “The Balkan Crisis: A Brief History,” CNN, 1997, https://www.cnn.com/SPECIALS/1997/bosnia/history/.
21. Mark Urban, “Bosnia: The Cradle of Modern Jihadism?,” BBC News, July 2, 2015, https://www.bbc.com/news/world-europe-33345618.
22. Apart from Al Kifah Refugee Center and Benevolence International Foundation, the International Islamic Relief Organization, the Third World Relief Agency, and the Islamic Cultural Institute in Milan all played major roles in recruitment, finance, money laundering, and transportation for the mujahedeen fighters in Bosnia.
23. Chris Hedges, “Foreign Islamic Fighters in Bosnia Pose a Potential Threat for G.I.’s,” New York Times, December 3, 1995, https://www.nytimes.com/1995/12/03/world/foreign-islamic-fighters-in-bosnia-pose-a-potential-threat-for-gi-s.html.
24. Hegghammer, “The Rise of Muslim Foreign Fighters,” 61.
25. Thomas Hegghammer, Jihad in Saudi Arabia (Cambridge: Cambridge University Press, 2010); Alison Pargeter, The New Frontiers of Jihad: Radical Islam in Europe (Philadelphia: University of Pennsylvania Press, 2008).
26. Hedges, “Foreign Islamic Fighters in Bosnia Pose a Potential Threat for G.I.’s.”
27. State Department, Dayton Peace Accords, November 21, 1995, https://www.state.gov/p/eur/rls/or/dayton/52578.html.
28. Urban, “Bosnia: The Cradle of Modern Jihadism?”
29. Carlotta Gall and Thomas de Waal, Chechnya: Calamity in the Caucasus (New York: NYU Press, 1999), 101–102.
30. Ibid., 99.
31. Ibid., xi.
32. Gazavat, or holy war, comes from the Arabic word “ghazi” or holy warrior. The term is roughly equivalent to jihad but historically associated with folk Islam and specifically in the Chechen context, with war against the Russians. Robert W. Schaefer, The Insurgency in Chechnya and the North Caucasus: From Gazavat to Jihad (Santa Barbara, CA: Praeger Security International, 2011), 56.
33. Moore and Tumelty, “Foreign Fighters and the Case of Chechnya,” 416.
35. Ibid., 417.
36. Lorenzo Vidino, “How Chechnya Became a Breeding Ground for Terror,” Middle East Quarterly 12, no 3 (Summer 2005): 57–66.
38. The civil war in Tajikistan, which lasted from 1992 to 1997, broke out one year after Tajikistan declared independence. The conflict was primarily between the Moscow-backed government and a liberal and Islamist opposition that received significant support from foreign fighters.
39. Murad Batal al Shishani, “Abu Mus’ab Al-Suri and the Third Generation of Salafi-Jihadists,” Terrorism Monitor 3, no. 16 (August 15, 2005), https://jamestown.org/program/abu-musab-al-suri-and-the-third-generation-of-salafi-jihadists/.
40. Hegghammer, “The Rise of Muslim Foreign Fighters,” 61.
41. Vadim Zaitsev, “Наемники В Чечне” [Mercenaries in Chechnya], Журнал “Огонёк,” March 21, 2011, https://www.kommersant.ru/doc/1604045.
42. Moore and Tumelty, “Foreign Fighters and the Case of Chechnya,” 418.
43. Ibid., 416.
44. Carlotta Gall, The Wrong Enemy (Boston, MA: Houghton Mifflin Harcourt, 2014), xiii.