A POLICY RESPONSE TO ISLAMIC STATE 

EXTREMIST FIGHTER BATTLEFIELD MIGRATION

Robert J. Bunker 

Alma Keshavarz

U.S. ARMY WAR COLLEGE
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US Army War College

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A POLICY RESPONSE TO ISLAMIC 

STATE EXTREMIST FIGHTER 

BATTLEFIELD MIGRATION

Robert J. Bunker and Alma Keshavarz

August 2020

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ISBN 1-58487-827-4
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US Army War College

FOREWORD

The subject of Islamic State extremist fighters 

returning to Western countries or laterally transferring 

to other global insurgent battlefields has increasingly 

come into international security and US defense policy 

discussions. Concerns from such discussions are 

derived from the territorial demise of the caliphate in 

December 2017 and the potentially large numbers of 

extremist fighters and their family members estimated 

to still reside in Islamic State enclaves in Syria and 

Iraq. Veteran fighters migrating back to their countries 

of origin in the West to engage in terrorist actions or 

to support insurgent operations in Africa or Central 

and Southeast Asia present a new phase in one 

component of the ongoing war with radical Sunni 

Islamist extremism.

This monograph by Dr. Robert J. Bunker and 

Dr. Alma Keshavarz examines the important subject 

of extremist fighter migration by first providing an 

overview of the Islamic State’s pedigree along with its 

precaliphate and transcaliphate territorial strategies, 

postcaliphate strategic potential, and demographic 

information. These discussions are followed by 

problem identification related to returning extremist 

fighters, inflows into Syria and Iraq, outflows to the 

United States and new battlefields overseas, and the 

special case of women and children.

The final component of the monograph provides a 

suite of counterbattlefield migration policy response 

options for United States Central Command to 

consider. Countermigration policies—focusing on 

the extremist fighters themselves and organizational 

components of the Islamic State—are then introduced 

and discussed. Finally, the need for these policy 
vi

US Army War College

responses to deconflict with greater US foreign policy 

imperatives in Syria and Iraq is emphasized, along 

with four Joint Force–focused recommendations.

This work provides grounded policies with which 

to combat the contemporary challenge of extremist 

fighter migration and highlights the ongoing relevance 

of Strategic Studies Institute publications to the 

changing twenty-first-century security environment 

that we, as citizens of our nation and representatives 

of our nation’s Army, are facing.

DR. CAROL V. EVANS

Director

Strategic Studies Institute and

US Army War College Press
vii

US Army War College

SUMMARY

June 2014 to December 2017 represented the high 

tide of radical Islamist (Salafi-jihadist) territorial 

control under the authority of the Islamic State in 

Iraq and Syria. Primarily battle-hardened, many 

fighters remain situated within the various enclaves 

still controlled by that hybrid terrorist-insurgent 

entity. This monograph analyzes and provides policy 

response options for US national security and Army 

planners concerning the potential for postterritorial 

caliphate battlefield migration by this still-sizable 

contingent of Islamic State foreign fighters. The 

monograph achieves these ends by

1. discussing Islamic State territorial eras and 

demographics;

2. offering an overview of the initial inflows of these 

fighters into the territorial caliphate, outflows to 

the United States, and lateral transfers to new 

battlefields, as well as mentioning special issues 

related to Islamic State women and children;

3. highlighting and analyzing the four strategic 

options available to the Islamic State in its 

postterritorial caliphate phase; and

4. offering senior US policy makers and planners 

options for counterbattlefield migration policy 

responses.

Islamic State strategic options encompass

1. reestablishing the caliphate;

2. accepting loss of territorial control and going 

to ground;

3. launching a new wave of jihad against the West 

(and Russia); and
viii

US Army War College

4. creating microcaliphates for global insurgency 

purposes, which is the most viable long-term 

approach for the group.

In turn, planning options are presented which 

pertain to response policies focused on extremists and 

the Islamic State as an organization and embedded 

within the context of higher-level US foreign policies 

toward Syria and Iraq. Additionally, recommendations 

for counterforeign terrorist fighter programs and the 

Joint Force are provided.

We should be cognizant—from a methodological 

perspective—that one of the ongoing issues plaguing 

analysis of the potential for lateral battlefield transfer 

by Islamic State foreign fighters—including their 

opening up of new battlefields in Europe and, to a far 

lesser extent, the United States—is the discrepancies, 

gaps, and inconsistencies inherent in data and 

estimates on the actual number of foreign fighters, both 

in the past and the present. To help alleviate part of 

this uncertainty, the monograph develops a qualitative 

schema to place the foreign fighter threat into context. 

This schema incorporates extremist type, commitment, 

and location conditionals to assign a threat ranking 

to foreign fighters and their families. Although this 

schema is an imperfect solution, the robust future 

development of such a continuum of threats—though 

outside the scope of this research—would further 

benefit US policy responses as well as the activities of 

counterforeign terrorist fighter programs.
1

A POLICY RESPONSE TO ISLAMIC STATE 

EXTREMIST FIGHTER BATTLEFIELD 

MIGRATION

INTRODUCTION

The demise of the core territorial Islamic State, the 

caliphate established in late June 2014 that eventually 

consisted of individual provinces spanning over 

17,000 square miles across Syria and Iraq with nearly 

8 million people under its mandate, is considered a 

positive achievement in contemporary international 

relations.1 This radical Islamist Sunni protostate, the 

extremist origins of which trace back to its al-Qaeda 

linkages in 1999 as Jama’at al-Tawhid wal-Jihad 

in Afghanistan, openly advocated torture, slavery, 

sectarian cleansing, and a host of other activities held 

anathema to liberal-democratic values. Ultimately, the 

territorial victory over the Islamic State was secured 

by an uneasy alliance of competing state and nonstate 

entities which could, at the very least, agree that the 

caliphate represented an existential threat to their 

collective regional interests.2

1. “Sunni Rebels Declare New ‘Islamic Caliphate,’” 

Al Jazeera, June 30, 2014, https://www.aljazeera.com

/news/middleeast/2014/06/isil-declares-new-islamic

-caliphate-201462917326669749.html; and Paul D. Shinkman, 

“ISIS by the Numbers in 2017,” US News & World Report, 

December 27, 2017, https://www.usnews.com/news/world

/articles/2017-12-27/isis-by-the-numbers-in-2017.

2. Daveed Gartenstein-Ross and Bridget Moreng, 

“Foreword: The Islamic State’s Growth and Misrule, and the 

Future of Violent Non-State Actors,” in Global Radical Islamist 

Insurgency: Al Qaeda and Islamic State Networks Focus: A Small 

Wars Journal Anthology, ed. Dave Dilegge and Robert J. Bunker 

(Bloomington, IN: iUniverse, 2016), 2: xxviii–xxix.
2

The second-order effects related to the decline and 

eventual fall of the caliphate at the hands of so many 

competing—and, at times, openly belligerent—entities 

focus on the migration potential of foreign fighters—

typically male, but in some instances, female—and 

familial extremists out of Syria and Iraq. Such potential 

stems from Islamic State extremists either migrating 

from the core Islamic State battlefield to another one 

in a different part of the world or returning to their 

country of origin to open it up as a new front as part 

of the global radical Islamist insurgency.3 This global 

insurgency is based in radical Sunni Islam (Salafi 

jihadism) and has its origins in Osama bin Laden’s 

declaration of jihad against the United States and Saudi 

Arabia in 1996, followed by the paradigm-shifting 

attack on the World Trade Center towers and the 

Pentagon in 2001.4 Since the emergence of the Islamic 

State and the development of a schism between the 

Islamic State and al-Qaeda—Abu Bakr al-Baghdadi 

(the second al-Baghdadi) of the Islamic State and 

Ayman al-Zawahiri of al-Qaeda struggled over the 

3. This issue is recognized within the US Army War College 

(USAWC) KSIL as “3.b.6 Assess options for preventing extremists 

from leaving one battlefield in one part of the world to join another 

in a different part of the world. (Extremist migration).” Charles A. 

Carlton, ed., Key Strategic Issues List (KSIL) 2018–2020 (Carlisle, 

PA: Strategic Studies Institute, USAWC Press, 2018), 16.

4. For the original declaration in Arabic and an English 

translation, see Al-Qaeda, “Declaration of Jihad against the 

Americans Occupying the Land of the Two Holiest Sites,” reference 

no. AFGP-2002-003676, n.d., https://ctc.usma.edu/harmony

-program/declaration-of-jihad-against-the-americans

-occupying-the-land-of-the-two-holiest-sites-original

-language-2/.
3

establishment of the caliphate—this insurgency has 

morphed into a dual organizational threat.5

Within this global insurgency context, the 

immediate imperative for US national security and 

Army planners vis-à-vis a postterritorial caliphate is to 

address the battlefield migration potential of a sizable 

contingent of battle-hardened Islamic State foreign 

fighters situated within various remaining enclaves in 

Syria and Iraq.6 Derived from the Army’s Key Strategic 

Issues List (KSIL) and seeking recommendations 

for counterextremist migration policy to be applied 

against these foreign fighters and their familial 

relations, the following research approach will be 

5. For basic time frames, see Zack Beauchamp, “The Syrian 

War: A History,” Vox, September 21, 2015, https://www.vox

.com/cards/syrian-refugees-war-assad/isis-founded. For a more 

in-depth analysis, see Patrick Cockburn, The Rise of Islamic State: 

ISIS and the New Sunni Revolution (New York: Verso, 2015); and 

Ali Soufan, Anatomy of Terror: From the Death of bin Laden to the 

Rise of the Islamic State (New York: W. W. Norton & Company, 

2017). The global disposition of the major al-Qaeda and Islamic 

State enclaves and their affiliated groups can be viewed in Figure 

2, “Al-Qaeda and Islamic State Violent Activity, 2016–2018,” in 

Seth G. Jones, America’s Counterterrorism Gamble (Washington, 

DC: Center for Strategic and International Studies [CSIS], July 

26, 2018), 4. For a perspective on the competing al-Qaeda and 

Islamic State strategic approaches, see table 13, “Al-Qaeda and 

Islamic State Strategic Approaches,” in Robert J. Bunker and 

Pamela Ligouri Bunker, Radical Islamist English-Language Online 

Magazines: Research Guide, Strategic Insights, and Policy Response

(Carlisle, PA: Strategic Studies Institute, USAWC Press, 2018), 

130–31.

6. Bethan McKernan, “Up to 30,000 ISIS Fighters Remain in 

Iraq and Syria, Says UN,” Independent, August 15, 2018, https://

www.independent.co.uk/news/world/middle-east/isis

-fighters-iraq-syria-un-report-jihadis-raqqa-iraq-a8492736.html.
4

undertaken to identify these recommendations.7 First, 

we provide an overview of the past Islamic State 

territorial strategies and identify present and future 

strategic options for this severely battered but not-yetdefeated entity, as well as supply basic demographic 

information. Second, we identify problems related to: 

(1) inflows into and outflows out of Syria and Iraq; and 

(2) women and children in the caliphate, with émigré 

number estimates given where applicable. Third, we 

survey the postcaliphate geopolitical situation visà-vis how it will influence the Islamic State’s present 

strategic options and discuss the most likely courses 

of action (COAs). Finally, we recommend a suite of 

battlefield migration policy options to better contain 

the Islamic State threat within Syria and Iraq and 

prohibit foreign fighter veterans from traveling to 

new global battlefields or back to their host countries 

to engage in potential terrorist actions. These 

policy options benefit from multiple counterforeign 

terrorist fighter (counter-FTF) programs and Joint 

7. Carlton, Key Strategic Issues List. Although not stated 

explicitly in the KSIL, Islamic State fighters migrating back to 

the United States or Europe would technically be joining another 

battlefield. Such a perspective is in line with official Islamic State 

communiqués provided in the Rumiyah online magazine series 

and by the Amaq News Agency in the Islamic State’s social 

media. Although Rumiyah ceased publication in November 2017 

with the loss of Islamic State sanctuaries in Syria, the Amaq News 

Agency was still releasing short videos and issuing statements 

as of August 2018. See, for example, Thomas Joscelyn, “Islamic 

State Video Purportedly Shows Youths Responsible for Attacks in 

Chechnya,” FDD’s Long War Journal, August 21, 2018, https://

www.longwarjournal.org/archives/2018/08/islamic-state

-video-purportedly-shows-youths-responsible-for-attacks-in

-chechnya.php.
5

Force recommendations related to the global radical 

Islamist threat.

ISLAMIC STATE TERRITORIAL ERAS AND 

DEMOGRAPHICS

The origins of the Islamic State trace back through 

a lineage of groups initially entwined with the street 

philosophy and activities of Abu Musab al-Zarqawi, 

the ruthless Jordanian firebrand known for his 

sectarian attacks inflicted upon Shia populations and 

his videotaped and widely publicized beheading of 

American contractor Nicholas Berg in May 2004.8

Under Zarqawi’s leadership, the organization was 

known as Jama’at al-Tawhid wal-Jihad from 1999 

through 2004 while in Afghanistan and, later, al-Qaeda 

in the Land of Two Rivers (more popularly known 

as al-Qaeda in Iraq) from 2004 into 2006, after he 

redeployed it to that field of battle. The Majlis Shura 

al-Mujahideen is also noted as having existed for a 

brief period as part of this lineage.9 After Zarqawi’s 

death in June 2006, the new al-Qaeda in Iraq leader, 

Abu Hamza al-Muhajir, pledged allegiance to Abu 

Omar al-Baghdadi (the first al-Baghdadi), the leader 

of the Islamic State in Iraq (ISI), resulting in al-Qaeda 

8. For an early history and psychological insights related 

to Zarqawi, see Jason M. Breslow, “Nada Bakos: How Zarqawi 

Went from ‘Thug’ to ISIS Founder,” PBS, May 17, 2016, 

https://www.pbs.org/wgbh/frontline/article/nada-bakos

-how-zarqawi-went-from-thug-to-isis-founder/.

9. See Aaron Y. Zelin, The War between ISIS and al-Qaeda for 

Supremacy of the Global Jihadist Movement, Research Notes no. 20 

(Washington, DC: The Washington Institute for Near East Policy, 

June 2014), 1. This group has alternatively been called “Majlis 

Shura al-Mujahideen fi al-Iraq” (Mujahideen Shura Council in 

Iraq). See Mahan Abedin, “Mujahideen Shura Council in Iraq: 

Fact or Fiction?,” Terrorism Focus 3, no. 12 (March 28, 2006).
6

in Iraq becoming ISI’s affiliate.10 During this period, 

the ISI focused its territorial expansion within Al 

Anbar Province, Iraq. In reaction to the ISI’s extreme 

policies, its forces were defeated by tribal and 

community elements in the fall of 2006 through the 

summer of 2007; this event later came to be known as 

the “Anbar Awakening.”11 The ISI, still entrenched in 

enclaves within the western regions of the country, 

then went through a period of crisis and rebuilding. 

With the death of Abu Omar al-Baghdadi (the first 

al-Baghdadi) in April 2010, Abu Bakr al-Baghdadi (the 

second al-Baghdadi) became the new leader of the 

organization a month later.12

With about 80 percent of ISI leadership either killed 

or captured by mid-2010, the second al-Baghdadi 

brought many formerly imprisoned Iraqi intelligence 

and military officers into the leadership of the 

organization to help replenish its ranks.13 With the 

10. Zelin, “The War between ISIS and al-Qaeda,” 1–4.

11. Gary W. Montgomery and Timothy S. McWilliams, ed., 

Al-Anbar Awakening (Quantico, VA: Marine Corps University 

Press, 2009), 2:13.

12. Anthony Shadid, “Iraqi Insurgent Group Names New 

Leaders,” New York Times, May 16, 2015, https://atwar.blogs

.nytimes.com/2010/05/16/iraqi-insurgent-group-names-new

-leaders/?_php=true&_type=blogs&_r=0.

13. “US Says 80% of al-Qaeda Leaders in Iraq 

Removed,” BBC News, June 4, 2010, https://www.bbc.co.uk

/news/10243585; and Liz Sly, “The Hidden Hand behind 

the Islamic State Militants? Saddam Hussein’s,” Washington 

Post, April 4, 2015, https://www.washingtonpost.com/world

/middle_east/the-hidden-hand-behind-the-islamic-state

-militants-saddam-husseins/2015/04/04/aa97676c-cc32-11e4

-8730-4f473416e759_story.html; and Isabel Coles and Ned Parker, 

“How Saddam’s Men Help Islamic State Rule,” Reuters, December 

11, 2015, https://www.reuters.com/investigates/special-report

/mideast-crisis-iraq-islamicstate/.
7

advent of the Syrian civil war in early 2011, the ISI 

sent many extremist fighters into Syria by August of 

that year to exploit the increasing absence of central 

authority. From late 2010 into early 2013, the ISI 

was able to restructure and reconstitute itself into 

its contemporary Islamic State form, and this was 

further facilitated by the final US troop withdrawals 

in late 2011.14 Although the Syrian civil war initially 

precipitated the influx of foreign fighters into the 

region with the intent to aid those affected by the 

Assad regime, between 2013 and 2014 a large group 

of these foreign fighters migrated into Syria and Iraq 

to fight for the Islamic State. From April 2013 on, 

with increasing Islamic State victories and the group 

further dissociating itself from al-Qaeda, three Islamic 

State territorial eras have been identified, along with 

an emergent one.

14. Security debates exist related to the US troop withdrawal 

and the ensuing Shia-dominated Iraqi government policies of 

Nuri al-Maliki that estranged the Sunni populace in the central 

and western regions of the country. See Alice Fordham, “Fact 

Check: Did Obama Withdraw from Iraq Too Soon, Allowing 

ISIS to Grow?,” NPR, December 19, 2015, https://www.npr

.org/2015/12/19/459850716/fact-check-did-obama-withdraw

-from-iraq-too-soon-allowing-isis-to-grow.
8

Table 1. Islamic State territorial strategies

PHASE STRATEGY TIME

PERIOD

EXAMPLES

1. Precaliphate • Initial territorial 

acquisition

• Terrorism

• Insurgency

• Hijrah (emigration) 

to Syria 

April 2013 to 

May 2014

• Large foreign fighter 

influx into Syria 

(2013–14)

• Growing Islamic State 

enclaves in Syria and 

Iraq

• Early Black Flags/

related e-books

2. Caliphate 

(Rise and 

Expansion)

• Baqiya wa tatamaddad

(remaining and 

expanding)15

• Hijrah (emigration) to 

Syria and Iraq

• Ghanimah (war booty) 

to expand

June 2014 to 

July 2016

• Repeated calls for 

foreign fighters to 

travel to the caliphate 

(actual fighter 

migration out in 

2015–16)

• Capture of Mosul; 

caliphate declared

• Dabiq online 

magazine

3. Caliphate 

(Decline and 

Fall)

• Jihad fard ‘ayn

(defensive holy war) 

in Iraq and Syria

• Jihad (holy war) 

against “the Romans”

• Hijrah (emigration) to 

the Philippines/other 

areas

August 2016 

to November 

2017 

• Foreign fighter 

migration in/out 

frozen

• Loss of Mosul and 

Al-Raqqah; territorial 

demise

• Rumiyah online 

magazine

4. Postcaliphate • Terrorism and 

insurgency via 

remnant enclaves

• Jihad (holy war) 

against “the Romans”

• New Wilayat

(provinces)/

microcaliphate 

creation

December 

2017 to

present

• Foreign fighter 

battlefield migration 

potential unknown

• Bay’ah (oath of 

allegiance) to leaders 

of groups still exist

• No digital magazines 

or e-books/localized 

narratives

Precaliphate

This era spanned roughly April 2013 through 

May 2014, just before the founding of the caliphate. 

The Islamic State capitalized on the political chaos 

15. See Cameron Glenn et al., “Timeline: The Rise, Spread, 

and Fall of the Islamic State,” updated October 28, 2019, https://

www.wilsoncenter.org/article/timeline-the-rise-spread-and

-fall-the-islamic-state. See also International Crisis Group, Facing 

the Challenge of the Islamic State in West Africa Province (Brussels: 

International Crisis Group, May 16, 2019).
9

of the Syrian civil war—including material support 

from foreign patrons seeking to overthrow the 

Assad regime—as well as weak state capacity in 

Iraq, magnified by sectarian political infighting. 

This territorial acquisition phase was derived from 

a combination of insurgency supported by acts of 

terrorism in which parallel governance—and, later, 

political and religious primacy—was established in a 

patchwork of Islamic State enclaves that, over time, 

began to merge toward one another. The Islamic State 

began to stress emigration by means of social media 

and videos, coupled with early e-books such as the 

Shuhada and the Black Flags series and the initial IS 

News and IS Reports.

By the beginning of 2013, global country estimates 

indicated a steady stream of fighters was flowing into 

the Syrian-Iraqi conflict zone.16 Characteristically, 

large numbers of foreign fighters arrived principally 

in Syria and were trained and outfitted to engage in 

operations there, or they laterally migrated into Iraq 

to support the enlargement of Islamic State enclaves 

in that country. A 2013 International Centre for the 

Study of Radicalisation report estimated that between 

2011 and early 2013, Europeans represented about 

“7–11 percent of the total foreign fighter population 

of between 2,000 and 5,500 persons.”17 The latter half 

of 2013, however, drew in larger numbers of fighters, 

16. The Soufan Group, Foreign Fighters: An Updated 

Assessment of the Flow of Foreign Fighters into Syria and Iraq (New 

York: The Soufan Group, December 2015).

17. Edwin Bakker and Mark Singleton, “Foreign Fighters 

in the Syria and Iraq Conflict: Statistics and Characteristics of 

a Rapidly Growing Phenomenon,” in Foreign Fighters under 

International Law and Beyond, ed. Andrea de Guttry, Francesca 

Capone, and Christoph Paulussen (New York: Springer, February 

2016), 14.
10

particularly from Europe. A 2014 Brookings report 

by Daniel Byman and Jeremy Shapiro indicates 

“this period witnessed the fastest mobilization of 

foreign fighters in the history of the modern jihadist 

movement.”18 The International Centre for the Study 

of Radicalisation report further estimated that by midDecember 2013, “there were up to 11,000 fighters from 

more than 70 countries that had joined the struggle in 

Syria against President Bashar al-Assad.”19

Toward the latter end of this period, as the enclaves 

began to merge into a territorial entity, families began 

to join the men who had gone before. Available 

information on foreign fighters from Germany, 

Belgium, and the Netherlands is illustrative in this 

regard. Antwerp and Brussels were known to have 

“clusters of likeminded militants” who were “drawn 

into the orbit of radical preachers who encouraged 

and facilitated their travel to fight jihad early on in 

the Syrian civil war.”20 Moreover, Belgium had a large 

population of North African Arab Muslims, an easily 

targeted demographic for Islamic State recruitment. 

As in Belgium, a large number of women are said to 

have left the Netherlands for Syria and Iraq in 2013 

and 2014 when the group called on women to “join 

18. Daniel Byman and Jeremy Shapiro, Be Afraid, Be a Little 

Afraid: The Threat of Terrorism from Western Foreign Fighters in 

Syria and Iraq, Policy Paper no. 34 (Washington, DC: Brookings 

Institution, November 2014).

19. Bakker and Singleton, “Foreign Fighters,” 14.

20. Pieter Van Ostaeyen, “Belgian Radical Networks and the 

Road to the Brussels Attacks,” CTC Sentinel 9, no. 6 (June 2016): 7.
11

their husbands who had traveled there.”21 Most Dutch 

émigrés are recorded to have returned before 2014, 

the majority of them being women. Further, some 

Dutch women who traveled abroad became pregnant, 

“making it difficult to verify how many children [had 

been] born in the conflict area,” particularly during 

this early period.22

Caliphate (Rise and Expansion)

From June 2014 through July 2016, the newly 

established caliphate was in its ascendancy. The 

territorial strategy expressed by the Islamic State 

during this era was derived from baqiya wa tatamaddad

(remaining and expanding) and supported by the 

taking of ghanimah (war booty)—literally billions of 

dollars’ worth of military equipment—to provide 

the Islamic State with a conventional ground combat 

capability. This rapid territorial expansion was 

witnessed following the capture of large Iraqi military 

stockpiles in cities such as Mosul (June 2014) and 

Ramadi (May 2015). The stockpiles provided the 

Islamic State with about three to four Iraqi Army 

divisions’ worth of equipment and materiel, which 

allowed the group’s extremist fighters to overrun 

defending Iraqi governmental and Syrian regime 

forces in outposts, towns, and cities throughout the 

21. Thomas Renard and Rik Coolsaet, “From the Kingdom 

to the Caliphate and Back,” in Returnees: Who Are They, Why 

Are They (Not) Coming Back and How Should We Deal with Them? 

Assessing Policies on Returning Foreign Terrorist Fighters in Belgium, 

Germany and the Netherlands, ed. Renard and Coolsaet, Egmont 

Paper 101 (Brussels: Egmont Institute, February 2018), 5.

22. General Intelligence and Security Service, Jihadist Women, 

a Threat Not to Be Underestimated (The Hague: General Intelligence 

and Security Service, November 2017), 6–7.
12

region and add their captured military equipment to 

the group’s growing military arsenal.23

The initial Islamic State online magazine Dabiq 

and supporting social media further promoted 

emigration to the lands of the caliphate in Syria and 

Iraq, particularly by those Muslims living in the 

West. Fighters and their families continued to arrive. 

A 2018 Combating Terrorism Center report analyzed 

documents retrieved from Islamic State-held territory 

and reported “1,100 women [had] registered in a 

guesthouse logbook operated by [the Islamic State] 

(assumed to be between 2014 and 2016).”24 The 

average age of female travelers was 29; 77 percent 

were married (compared to 30 percent of men), and 10 

23. The initial estimate of three divisions’ worth of materiel 

is attributed to Anthony H. Cordesman, CSIS, in a 2014 Wall 

Street Journal interview. See Matt Bradley, “Insurgents in Iraq 

Seizing Advanced Weaponry,” Wall Street Journal, July 6, 2014, 

https://www.wsj.com/articles/insurgents-in-iraq-seizing

-advanced-weaponry-1404684313, quoted in Jeremy Bender, 

“As ISIS Routs the Iraqi Army, Here’s a Look at What the 

Jihadists Have in Their Arsenal,” Business Insider, July 8, 2014, 

https://www.businessinsider.com/isis-military-equipment

-breakdown-2014-7. This estimate was increased to possibly four 

divisions worth of materiel the following year. See Chris Lo, 

“Friendly Fire: Accounting for the Stolen Arsenal of ISIS,” Army 

Technology, February 1, 2016, https://www.army-technology

.com/features/featurefriendly-fire-accounting-for-the-stolen

-arsenal-of-isis-4789324/.

24. Daniel Milton and Brian Dodwell, “Jihadi Brides? 

Examining a Female Guesthouse Registry from the Islamic State’s 

Caliphate,” CTC Sentinel 11, no. 5 (2018). See also Joana Cook 

and Gina Vale, From Daesh to ‘Diaspora’: Tracing the Women and 

Minors of Islamic State (London: International Centre for the Study 

of Radicalisation, King’s College London, July 2018), https://icsr

.info/2018/07/23/from-daesh-to-diaspora-tracing-the-women

-and-minors-of-islamic-state/.
13

percent were single (compared to 61 percent of men).25

Islamic State propaganda appealed to both genders 

by offering a life of financial stability, health care and 

education, community support, independence, and 

adventure. Although a significantly large number 

of women have traveled voluntarily, some were 

“likely coerced and, in some cases, forced to travel.”26

Women who were actively involved often recruited 

other women, spread Islamic State propaganda, and 

fundraised for the group.

Until 2015, experts believed more than 200 young 

women and teenage girls had traveled to join the 

Islamic State from Europe. The majority were from 

France (60), followed by the United Kingdom (50), 

Germany (40), Belgium (35), and Austria (14).27 An 

International Centre for Counter-Terrorism (ICCT) 

report from 2016 indicated that 17 percent of “the total 

European contingent” were female foreign fighters.28

European women traveling to the conflict zone often 

married an Islamic State member online before their 

arrival; others were married just as they arrived. 

Women were also believed to be indoctrinating their 

children with jihadist ideology.29

Émigrés came from other parts of the world, 

including parts of Asia and even North America, 

although in smaller numbers. Such foreign fighter 

travel continued through most of 2014, but reversed 

itself in 2015, decreasing steadily through 2016. 

25. Cook and Vale, From Daesh to ‘Diaspora’, 23–24.

26. Cook and Vale, From Daesh to ‘Diaspora’, 26.

27. Cook and Vale, From Daesh to ‘Diaspora’, 26.

28. Tanya Mehra, Foreign Terrorist Fighters: Trends, Dynamics 

and Policy Responses (The Hague: ICCT, December 2016), 11.

29. Renard and Coolsaet, “From the Kingdom to the 

Caliphate,” 22.
14

This reversal resulted from a secondary outflow of 

migration from the caliphate stemming from the 

primitive living conditions that existed there and the 

increasing US and allied air strikes taking place at that 

time. Many foreign fighters returned to their countries 

of origin beginning in 2015, with the highest numbers 

returning in mid-2015. Some returned “disillusioned 

and frustrated with their situation”; others returned 

because of “calls by family and friends.”30

The 2018 annual Department of State country 

reports on terrorism referred to Turkey as a “source 

and transit country for FTFs seeking to join [the Islamic 

State of Iraq and Syria (ISIS)] and other terrorist groups 

fighting in Syria and Iraq.”31 Because many foreign 

fighters used Turkey as the gateway to the conflict 

zone, Turkey “established risk analysis units at airports 

and border crossing points and had a comprehensive 

no-entry list in place.”32 This perspective on Turkey 

interdicting Islamic State foreign fighter inflows and 

outflows, though, can be contrasted to earlier—and 

still legitimate—allegations that it allowed Islamic 

State fighters into Syria in 2015 to fight the Kurds and 

use Turkish regions as logistics bases.33 Still, since 

mid-2015, the number of individuals from the United 

States traveling to or attempting to travel to the conflict 

zone declined, which officials believe resulted from 

“Turkey’s increased border security, deterrence from 

arrests in the United States, ISIS’s encouragement that 

30. Daniel H. Heinke and Jan Raudszus, “Germany’s 

Returning Foreign Fighters and What to Do about Them,” in 

Renard and Coolsaet, Returnees, 44.

31. Bureau of Counterterrorism, Country Reports on Terrorism 

2018 (Washington, DC: US Department of State, October 2019).

32. Mehra, Foreign Terrorist Fighters, 6.

33. See Daniel Byman, “How States Exploit Jihadist Foreign 

Fighters,” Studies in Conflict & Terrorism 41, no. 12 (2018): 4–5.
15

supporters commit attacks at home, and the group’s 

ongoing battlefield losses.”34 Still, these numbers were 

never above the low hundreds.

Caliphate (Decline and Fall)

The territorial ISIS promoted itself as engaging 

in a defensive holy war on all fronts from August 

2016 through November 2017. A major loss to the 

caliphate was the conquest of Mosul in June 2017 by 

a US-backed coalition of Iraqi governmental units, 

Kurds, and Shia fighters.35 This conquest was followed 

by increasing manpower, materiel, and geographic 

losses by the Islamic State, culminating in its last 

strongholds and capital being overwhelmed over the 

ensuing months. As the Islamic State lost territory, 

Iraqi and Kurdish forces in the country captured a 

large number of its women and minors. By September 

2017, approximately 1,400 women and children of 

“presumed [Islamic State] fighters were held in a camp 

south of Mosul, according to media reports relying 

on sources in Iraqi intelligence”; this figure included 

European nationals.36

The number of jihadists attracted to the Islamic 

State was also in significant decline. In 2017, the US 

34. Countering Violent Extremism Task Force, “Reference 

Aid: US Foreign Fighters,” September 2017, https://www.dhs

.gov/sites/default/files/publications/Foreign%20Fighters

_CVE%20Task%20Force_Final.pdf.

35. Isabel Coles and Stephen Kalin, “Iraqi PM Declares 

Victory over Islamic State in Mosul,” Reuters, July 10, 2017, 

https://www.reuters.com/article/us-mideast-crisis-iraq

-mosul/iraqi-pm-declares-victory-over-islamic-state-in-mosul

-idUSKBN19V105.

36. EU Agency for Law Enforcement Cooperation (EUROPOL), 

European Union Terrorism Situation and Trend Report (TE-SAT) 2018

(The Hague: EUROPOL, 2018), 36.
16

intelligence community indicated “the number of 

foreign fighters crossing the border from Turkey 

fell from 2,000 each month [in 2015] to about 50 in 

September 2016.”37 Turkey seemingly did its part to 

prevent the further flow of migration into Syria and 

Iraq and stop foreign fighters attempting to return 

to their countries of origin. Because the Islamic State 

faced a series of defeats in Iraq and Syria, the number 

of foreign fighter returnees was also low in 2017.38

For example, when returnees began to be recorded 

in Belgium between 2013 and 2015, the numbers 

indicated the flow of returnees had slowed in 2016 

and 2017, when only a few families with children 

returned.39

The International Criminal Police Organisation 

(INTERPOL) established a database that continues 

to keep track of foreign fighter travelers and that has 

further facilitated states’ efforts to prevent the fighters’ 

migration from the Islamic State. This database 

comprises 7,500 records. The number of names 

and countries of origin in the database continued to 

rise well into 2017.40 Law enforcement agencies in 

numerous countries have in large part cooperated to 

contain the threat of foreign fighter returnees via UN 

37. Alastair Reed, Johanna Pohl, and Marjolein Jegerings, 

The Four Dimensions of the Foreign Fighter Threat: Making Sense of 

an Evolving Phenomenon (The Hague: ICCT, June 2017), 4. See also 

Soufan Group, Foreign Fighters, 10.

38. EUROPOL, TE-SAT 2018, 6.

39. Renard and Coolsaet, “From the Kingdom to the 

Caliphate,” 21.

40. Renard and Coolsaet, “From the Kingdom to the 

Caliphate,” 21. See also “INTERPOL Joins Global Coalition 

to Counter ISIL,” INTERPOL, July 22, 2016, https://

www.interpol.int/en/News-and-Events/News/2016

/INTERPOL-joins-Global-Coalition-to-Counter-ISIL.
17

and other internationally sponsored programs. Many 

states, such as Austria, Australia, Bahrain, Belgium, 

Canada, the Netherlands, and the United Kingdom, 

have enacted new laws that prevent foreign fighters 

from returning by revoking their citizenship, and in a 

host of other states, returnees from Syria and Iraq are 

subject to severe criminal penalties.41

As the caliphate was in its twilight during this era, 

jihad (holy war) against the unbelievers in the West 

was increasingly being advocated in its new online 

magazine Rumiyah. Rumiyah replaced Dabiq (the 

namesake town of which had been lost) and introduced 

its Just Terror Tactics series, similar to the Open Source 

Jihad series in Inspire, the earlier al-Qaeda online 

magazine. The concept of hijrah (emigration) also was 

broadened in Islamic State propaganda to include the 

encouragement of relocation to new provinces, such 

as in the Philippines. Notably, foreign fighter and 

family inflows and outflows related to Syria and Iraq 

during the latter part of this era dropped to a trickle 

as the access points became less permeable. Turkey 

reportedly deported 3,500 individuals suspected of 

being foreign fighters in July 2016 and denied entry to 

another 2,200 over the course of 18 months.42 At the 

same time, the tendency of extremist fighters to stand 

their ground and die in the defense of the caliphate 

during this period rather than withdraw from the 

41. Human Rights Watch, “‘Foreign Terrorist Fighter’ Laws: 

Human Rights Rollbacks under UN Security Council Resolution 

2178” (white paper, Human Rights Watch, December 2016), 14.

42. Mehra, Foreign Terrorist Fighters, 6.
18

battle or to their home countries also limited battlefield 

migration levels.43

Postcaliphate

Following the fall of Al-Raqqah in December 

2017 and Syria in October and the Iraqi declaration 

of victory over the Islamic State two months later 

was a period of strategic and territorial uncertainty 

for the remnants of the caliphate.44 Potential exists 

for the Islamic State to revert back to its precaliphate 

condition of the 2013 era in which its remaining 

fighters (and their families) simply went underground 

in Syria and Iraq and reverted back to terrorism and 

insurgency operations.45

Another potential is for lateral battlefield 

migrations to take place either nearby—to reinforce 

Islamic State groups in Libya, the Sinai Peninsula, or 

Saudi Arabia—or farther afield in such locales as East 

Africa, Afghanistan, Bangladesh, or the East Indies, 

where microcaliphates are attempting to emerge.

The third potential, and the greatest concern for the 

United States and its Western allies, is those extremist 

fighters originating from the West will migrate back 

home and take the jihad philosophy to heart by 

43. Counter-Terrorism Committee Executive Directorate, 

The Challenge of Returning and Relocating Foreign Terrorist Fighters: 

Research Perspectives (New York: Counter-Terrorism Committee 

Executive Directorate, March 2018), 3.

44. Maher Chmaytelli and Ahmed Aboulenein, “Iraq Declares 

Final Victory over Islamic State,” Reuters, December 9, 2017, 

https://www.reuters.com/article/us-mideast-crisis

-iraq-islamicstate/iraq-declares-final-victory-over-islamic-state

-idUSKBN1E30B9.

45. For thoughts on this option, see Thomas R. McCabe, “The 

Islamic State after the Caliphate—Can IS Go Underground?,” 

Perspectives on Terrorism 11, no. 4 (August 2017): 95–101.
19

standing up operational cells and conducting increased 

attacks against the countries’ civilian populations. 

Such attacks could take place independently of, or in 

tandem with, Islamic State lone-wolf attacks. Quite 

possibly, all three postcaliphate strategic reorientations 

will initially exist simultaneously. The potential 

viability of some of these strategic approaches will 

be dependent on the extremist fighter and familial 

demographics and the contemporary postcaliphate 

geopolitical situation in which the Islamic State has 

now found itself.

Although a fourth potential, Islamic State and 

al-Qaeda rapprochement, has been discussed in some 

international security circles, this possibility is not 

viewed as viable at present. Although affiliate group 

defection has continued from time to time, the two 

organizations’ ideological perspectives on relations 

with Shia populations, practices such as beheadings, 

leadership bound by feudal-like alliance structures 

down to their chieftains and war leaders, and other 

issues have increasingly differed. A rapprochement 

could theoretically take place if the top Islamic State 

or al-Qaeda leadership were eliminated. In such 

an instance, all the bay’ahs (alliances) holding the 

organization together would be nullified because they 

exist at an individual fealty (vassal to lord) level.46

The Islamic State has largely been pushed out of 

large expanses of Syria and Iraq, but, at the same time, 

46. For differing perspectives on Islamic State and 

al-Qaeda relations, see Scott Stewart, “Can the Islamic State and 

al Qaeda Find Common Ground?,” Stratfor Worldview, March 

9, 2017, https://worldview.stratfor.com/article/can-islamic

-state-and-al-qaeda-find-common-ground; and Bruce Hoffman, 

“The Coming ISIS–al Qaeda Merger,” Foreign Affairs, March 

29, 2016, https://www.foreignaffairs.com/articles/2016-03-29

/coming-isis-al-qaeda-merger.
20

pockets of fighters remain in the two countries, as does 

the threat of returning foreign fighters. According 

to the UN’s July 2018 report on the Islamic State, the 

current total number of Islamic State membership 

in Syria and Iraq is estimated to be between 20,000 

and 30,000.47 The Department of Defense has not 

commented on the accuracy of these new numbers, 

nor has any official provided further estimates. A 

lot of uncertainty exists, leaving no way to validate 

the accuracy of these numbers, so they should be 

considered only generalizations related to present 

Islamic State fighter strength.

PROBLEM IDENTIFICATION

To better understand the concerns related to 

extremist fighter migration coming out of Syria and 

Iraq, this section provides an overview of the initial 

inflows of these fighters into the territorial caliphate, 

outflows to the United States, and lateral transfers to 

new battlefields, and highlights special issues related 

to Islamic State women and children. Domestic 

concerns focusing on Islamic State fighters migrating 

back to the United States are minimal, with the real 

concern being that of lateral battlefield transfers to 

47. UN Security Council, Twenty-Second Report of the Analytical Support and Sanctions Monitoring Team Submitted Pursuant to Resolution 2368 (2017) Concerning ISIL (Da’esh), Al-Qaida 

and Associated Individuals and Entities, S/2018/705 (New York: 

UN Security Council, July 2018), 3, https://www.un.org

/en/ga/search/view_doc.asp?symbol=S/2018/705&referer=/

english/&Lang=E.
21

Islamic State provinces as well as very real returning 

fighter terrorism-based threats to our European allies.48

Inflows (Émigrés) to Syria and Iraq

Estimates of the total number of foreign fighters 

who have traveled to Syria and Iraq since the start of 

the conflict mostly range between 27,000 and 31,000; 

other estimates go as high as 40,000.49 An International 

Centre for the Study of Radicalisation report from 

July 2018 used a dataset from April 2013 and June 

2018 from official government sources and figures on 

foreign fighters, and, in cases where such data was 

not available, the authors used academic, institutional 

publications and media reports.50 The authors estimate 

that, over the 5-year period, a total of 41,490 foreign 

fighters emigrated to the caliphate from 80 different 

countries. Figure 1 shows estimates of the foreign 

fighter breakdown by region.51

48. Even though this threat to the US homeland—along with 

foreign national-derived terrorist threats—is relatively minor, it 

is still considered significant enough that various barrier-to-entry 

programs have gone into effect. See, for instance, Exec. Order No. 

13,769, 82 Fed. Reg. 8977 (Jan. 27, 2017).

49. Alexander Meleagrou-Hitchens et al., The Travelers: 

American Jihadists in Syria and Iraq (Washington, DC: Program on 

Extremism, February 2018), 5. See also Zack Fellman et al., Fallout: 

The Future of Foreign Fighters (Washington, DC: CSIS, 2017), 6.

50. Cook and Vale, From Daesh to ‘Diaspora’, 11.

51. All data are estimates derived from Cook and Vale, From 

Daesh to ‘Diaspora’, 14–15.
22

Figure 1. Foreign fighters by region, 2013–18

Most foreign fighter travel occurred through 

Turkey because of its border with Syria and “visa-free 

travel agreements with more than 69 governments, 

which limit the requirement for traveler screening.” 

In addition, “no visas are required for most EU 

citizens, some of whom are also able to travel on 

identity cards.”52 Other Europeans traveled through 

the Balkan states, the Caucasus, and then Iran, Russia, 

or Georgia into Turkey.53 Turkey recorded 53,781 

individuals “who were feared to [have attempted] 

to join the fight in Syria and Iraq” from information 

provided from 146 states.54 Tunisia, Saudi Arabia, and 

Morocco are noteworthy because of high numbers of 

52. Countering Violent Islamist Extremism: The Urgent 

Threat of Foreign Fighters and Homegrown Terror, 114th Cong. 

(2015) (statement of Nicholas J. Rasmussen, director of 

the National Counterterrorism Center).

53. Countering Violent Islamist Extremism (statement of 

Rasmussen).

54. Mustafa Gurbuz, “The Many Complications of 

Returning Islamic State Fighters,” March 19, 2018, http://

arabcenterdc.org/policy_analyses/the-many-complications

-of-returning-islamic-state-fighters/.

0 2,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 18,000 20,000

MENA

Europe

S & SE Asia

Central Asia

Americas, Australia, New Zealand

MENA Europe S & SE Asia Central Asia Americas, Australia, New Zealand

Returned 3,906 2,549 464 338 97

Traveled 18,852 13,156 1,510 5,965 753
23

failed attempts by citizens seeking to join the Islamic 

State in Syria and Iraq. Tunisian authorities stopped 

over 12,000 individuals and placed a further 4,605 

Tunisians on the country’s watch list. More than 7,000 

Saudi Arabians and nearly 3,000 Moroccan citizens 

were stopped by Turkish security elements.55 Thus, 

although the number of foreign fighters who traveled 

to the territorial caliphate is significant, the actual 

numbers could have been even larger.

Outflows (Returnees) to the United States

The number of foreign fighters emigrating to Syria 

and Iraq from the United States and their potential 

return are a direct national security concern. Unlike 

many other countries, the United States has had a 

relatively low level of Islamic State radicalization and 

recruitment of its citizens for emigration purposes into 

the caliphate. Between 5,000 and 7,000 individuals are 

said to have traveled to Syria and Iraq between 2011 

and 2016 from Europe alone, mostly from France, 

Belgium, Germany, and the United Kingdom.56 The 

number of Europeans actually fighting in the conflict 

zone by late 2017 was estimated to be around 2,500.57

The estimated number of foreign fighter-related 

émigrés from the United States, which is quite low 

in comparison, ranges from 250 to 300.58 According 

to the Countering Violent Extremism Task Force, 

“approximately three dozen Americans have died after 

55. Gurbuz, “Returning Islamic State Fighters.”

56. Fellman et al., Fallout: The Future of Foreign Fighters; and 

Brian Michael Jenkins, “Foreword,” in Meleagrou-Hitchens et al., 

Travelers, x.

57. EUROPOL, TE-SAT 2018, 26.

58. Jenkins, “Foreword,” x.
24

traveling to partake in this conflict.”59 Of the returnees 

to the United States, some have been arrested and 

prosecuted, but the status of others remains unknown. 

The average age of individuals leaving the United 

States for foreign jihadist fighting purposes was 27. Of 

the estimated 250–300 such travelers, 86 percent were 

adult males. Thus far, “44 percent are still at large or 

their status is publicly unavailable, 19 percent were 

apprehended in the US or overseas, 34 percent died 

overseas, and 5 percent returned to the US without 

facing charges.”60 The states with the highest numbers 

of émigrés were Minnesota, Virginia, and Ohio.61 See 

table 2 for a breakdown of North American Islamic 

State foreign fighter estimates by country (United 

States and Canada).62

Table 2. North American Islamic State foreign 

fighter estimates, 2014–17

COUNTRY TRAVELED RETURNED / %

United States 272 40/14.71%

Canada 90 17/18.89%

TOTALS 362 57/15.74%

Even if some of the estimated 110–32 Islamic 

State foreign fighters from the United States who 

are unaccounted for return home without being 

apprehended, their intent to engage in terrorist 

actions is not a certainty. According to a 2017 RAND 

study, returnees can be categorized into the following 

59. Countering Violent Extremism Task Force, 

“Reference Aid.”

60. Meleagrou-Hitchens et al., Travelers, 16.

61. Meleagrou-Hitchens et al., Travelers, 5.

62. Cook and Vale, From Daesh to ‘Diaspora’, 21.
25

three subgroups: disillusioned, disengaged but not 

disillusioned, and operational.63

The disillusioned subgroup traveled to the 

conflict zone in search of “utopia, adventure, and a 

pure expression of religious identity, but they found 

something far different.”64 This subgroup experienced 

harsh living conditions with very little food and 

money, psychological pressure from witnessing the 

trauma of the conflict, and a general lack of respect 

from locals. When this subgroup returned to its 

country of origin, potentially “these individuals 

[could] mentor other radicalized youth.”65

The second subgroup is not as disillusioned as the 

first; rather, it returned primarily for familial reasons. 

Although these individuals have grown weary of 

war and its deprivations, they are “still committed 

to jihadism.”66

The operational subgroup are individuals who 

want to create their own network of jihadists by 

recruiting new members to conduct attacks in 

their home countries to open up new Islamic State 

battlefields. As indicated by the RAND report, “these 

individuals are the most dangerous and deadly.”67

So when Islamic State foreign fighters return to the 

United States, the skill sets they possess translate into 

potentially more lethal attacks. Counterintuitively, 

however, such returnee foreign fighters being 

63. The Terrorist Diaspora: After the Fall of the Caliphate, 115th 

Cong. (2017) (statement of Colin P. Clarke, adjunct senior political 

scientist at the RAND Corporation).

64. Terrorist Diaspora, 5.

65. Terrorist Diaspora, 5.

66. Terrorist Diaspora, 5.

67. Terrorist Diaspora, 5.
26

involved in a plot or attack also lowers the plot or 

attack’s chances for success:

The presence of a returnee decreases the likelihood that an 

executed plot will cause mass casualties [based on 1990–

2017 data]. . . . Plots carried out with American returnees 

from Islamist insurgencies abroad also decrease the 

likelihood that a plot will come to fruition. The presence 

of a known foreign fighter increases the likelihood of 

detection and disruption by law enforcement officials.68

Given the low numbers of potential Islamic State 

fighters returning to the United States, that only a 

percentage of them would be operational, and that they 

would be monitored by law enforcement, the threat 

potential for extremist fighter migration is relatively 

low for the United States. To date, extremist fighter 

migration is still only a hypothetical threat because 

no Islamic State returnees have been involved in any 

such attacks. The closest such an attack has come to 

taking place was in April 2015 when Abdirahman 

Sheik Mohamud—an operative of the Al-Nusrah 

Front to Protect the Levant linked to al-Qaeda who 

had been sent back to the United States—was arrested 

while in the planning stages of an attack that was to 

take place in Texas.69 Because of the low numbers 

68. Christopher J. Wright, “Sometimes They Come Back: 

Responding to American Foreign Fighter Returnees and Other 

Elusive Threats,” Behavioral Sciences of Terrorism and Political 

Aggression 12, no. 1 (April 23, 2018): 1.

69. Jeff Seldin, “Study Finds Minimal Short-Term Threat 

from US Foreign Fighters,” VOA News, February 6, 2018, 

https://www.voanews.com/a/george-washington-university

-study-on-us-travelers/4240809.html; and Andrew Welsh

Huggins, “Man Apologizes, Sentenced to 22 Years for US 

Terrorism Plot,” Seattle Times, January 21, 2018, https://

www.seattletimes.com/nation-world/ohio-man-accused

-of-plotting-us-attacks-to-be-sentenced/.
27

and close monitoring by law enforcement, concerns 

over an Islamic State terrorist diaspora engaging in 

attacks domestically are overstated, unlike the threat 

facing Europe. But if such a veteran Islamic State 

fighter or a group of fighters could make it back into 

the United States without being detected, their combat 

skills would mean they would be able to engage in a 

terrorist attack far deadlier than that of homegrown 

extremists who had never traveled overseas to fight 

for the caliphate. Such returning foreign fighters 

have explosive and firearm skill sets, as opposed 

to local extremists who have been exposed to the 

Islamic State Just Terror Tactics presented in Rumiyah 

online magazine and who focus more on knife and 

vehicular attacks.70

Outflows (Laterals) to New Battlefields

Although we know the Islamic State strategically 

seeks to send forces into its immediate and more 

distant provinces representative of microcaliphate 

territories, our actual understanding of this dynamic 

is limited:

While we know that [the Islamic State] has established 

a presence in Libya, Yemen, Afghanistan, Egypt, [and] 

perhaps elsewhere, such as the Philippines, we have only 

fragmentary information on whether these forces are 

being reinforced by fighters from Syria and Iraq . . . This 

is in part because the internal operations and decisionmaking processes of [the Islamic State] remain opaque, 

70. For a discussion of these tactics and attacks linked to 

them, see Robert J. Bunker and Pamela Ligouri Bunker, The Islamic 

State English-Language Online Magazine Rumiyah (Rome): Research 

Guide, Narrative & Threat Analysis and US Policy Response (Reston, 

VA: The Terrorism Research Center, August 2019).
28

and the status of its leadership and remaining fighters is 

largely unknown.71

Still, specific instances of these fighters having engaged 

in lateral battlefield migration—from Syria, Iraq, and 

other regions—have been reported:

The [Islamic State of Iraq and the Levant (ISIL)] core 

continues to facilitate the relocation of some of its key 

operatives to Afghanistan. One Member State reports 

that foreign terrorist fighters who are nationals of Algeria, 

France, the Russian Federation, Tunisia and Central 

Asian States have recently arrived in Afghanistan, and 

that Abu Qutaiba, the ISIL leader in Salah al-Din Province 

of Iraq, has reportedly relocated to Badakhshan Province 

of Afghanistan.72

These strategic shifts had been duly communicated to 

ISIS-affiliated terrorists and supporters in the region. In 

recent weeks, online Daesh sympathizers have begun 

popularizing the terms Wilayah al-Filibin and Wilayah 

Asia Timur (Malay: East Asia Province) using them 

interchangeably. . . . As a result, new groups have formed 

with the idea that they would have to accommodate 

foreign fighters into their ranks.73

71. Lorne L. Dawson, The Demise of the Islamic State and the 

Fate of Its Western Foreign Fighters: Six Things to Consider (The 

Hague: ICCT, June 2018), 2–3.

72. UN Security Council, “Letter Dated 16 July 2018 from the 

Chair of the Security Council Committee Pursuant to Resolutions 

1267 (1999), 1989 (2011) and 2253 (2015) Concerning Islamic 

State in Iraq and the Levant (Da’esh), Al-Qaida and Associated 

Individuals, Groups, Undertakings and Entities Addressed to the 

President of the Security Council,” UN Digital Library, July 16, 

2018, https://digitallibrary.un.org/record/3813209?ln=en.

73. Jasminder Singh and Muhammad Haziq Jani, “ISIS 

in East Asia: Strategic Shifts and Security Implications,” RSIS 

Commentary no. 090, May 11, 2017, (italics in original), https://

www.rsis.edu.sg/wp-content/uploads/2017/05/CO17090.pdf.
29

By November 2017, after the loss of 95 percent of its 

caliphate, ISIS still had more than three dozen wilayats, 

or provinces, on three continents. Some were small. Some 

were dormant. But all have been deadly. Many fighters 

fleeing the caliphate were opting to travel to established 

branches or wilayats in third-countries rather than 

returning to countries of origin.74

It is reported that some foreign fighters who leave Sirte 

[Libya], on the one hand are heading south to possibly 

join the group Boko Haram and, on the other hand some 

are going west to Tunisia.75

One of the wilayat mentioned above and other 

regions, “including Libya, the Sinai Peninsula, 

Afghanistan, Yemen, the Philippines and several 

regions across Africa,” have the potential to become 

the new Islamic State headquarters.76 If such a 

contingency were allowed to happen, the Islamic 

State or a newly updated form of the group would be 

able to begin to reconstitute itself in a new safe haven 

for the next phase of the ongoing radical Islamist 

global insurgency.

Even with the many unknowns related to extremist 

fighter migration from Syria and Iraq to lateral 

battlefields, we can accurately state this phenomenon 

presently represents a far greater level of concern to 

the global security interests of the United States and 

74. “ISIS after the Caliphate,” Woodrow Wilson 

International Center for Scholars, updated January 8, 2018, 

https://www.wilsoncenter.org/article/isis-after-the-caliphate-0.

75. Claudio Bertolotti, “Islamic State’s Foreign Fighters: 

There and Back,” Osservatorio Strategico 19, no. 1 (2017): 55.

76. Colin P. Clarke, “Where Will ISIS Seek to Establish 

Its Next Safe Haven?,” Jerusalem Post, February 19, 2018, 

https://www.jpost.com/opinion/where-will-isis-seek

-to-establish-its-next-safe-haven-542967.
30

the US Army than Islamic State fighters returning 

directly to our homeland.77 On one hand, we have less 

than 150 individuals from this threat group who are 

unaccounted for and who could potentially reenter 

the United States, with no acts of domestic terrorism 

by such fighters having been documented in the past. 

On the other hand, we have thousands of foreign 

fighters who may potentially seek to bolster Islamic 

State enclaves throughout various regions of the globe. 

Although many of these fighters may seek to fight until 

the end in Syria and Iraq, and others have attempted or 

will attempt to migrate back to various European and 

Middle Eastern and North African countries not yet 

engulfed in Islamic State insurgencies, a substantial 

portion of these individuals will likely seek to engage 

in lateral battlefield transfers. The establishment of 

new Islamic State provinces and the reinforcement 

of older ones with fresh fighters migrating into them 

would result in more acts of terrorism as well, enabling 

the groundwork for new insurgencies to form. New 

insurgencies would represent a direct threat to US 

interests and would perhaps require boots on the 

ground, as has taken place in Iraq, Afghanistan, Syria, 

and other locales.

The Special Case of Women and Children

About 14 percent of the foreign fighters and family 

members—38 individuals—who traveled to Syria and 

Iraq from the United States were adult females, a small 

percentage of the estimated 4,761 women who reside 

77. For an overview of initial American citizen involvement 

with the Islamic State, see Robert Pape et al., The American Face 

of ISIS: Analysis of ISIS-Related Terrorism in the US, March 2014—

August 2016 (Canberra, Australia: Australian Strategic Policy 

Institute, February 2, 2017).
31

in the caliphate.78 Based on overall statistics related 

to women and girls joining the Islamic State, many 

of them were led to believe the caliphate would give 

their lives meaning; others joined for pure excitement. 

Teenage girls left in hopes of “marrying a ‘warrior.’”79

Upon arrival, both single and married women were 

sent to stay at a “women’s house” until they were 

married or the husband they traveled with “passed 

his interrogation and completed his training.”80 The 

age range for women and girls was typically between 

16 and 24, but girls as young as 13 were found to be 

seeking to travel to Islamic State-held areas in Syria 

after radicalization.81 Women also traveled to Syria 

and Iraq to join their husbands “or were motivated 

by revenge for loss of their husbands or relatives.”82

As the conflict progressed and the Islamic State’s 

propaganda machine strengthened, women and girls 

“left their homes to marry jihadists, mostly foreign 

fighters who they had found on the Internet, after being 

convinced of the need to support the fighters and bear 

their children to create conditions for the growth and 

normal functioning of the new proclaimed caliphate, 

as well as to contribute in women’s traditional roles in 

78. Cook and Vale, From Daesh to ‘Diaspora’, 14, 20.

79. Marije Meines et al., RAN Manual: Responses to Returnees: 

Foreign Terrorist Fighters and Their Families (Amsterdam: 

Radicalisation Awareness Network Centre of Excellence, July 

2017), 21.

80. General Intelligence and Security Service, Jihadist 

Women, 6.

81. Anita Peresin and Alberto Cervone, “The Western 

Muhajirat of ISIS,” Studies in Conflict & Terrorism 38, no. 7 (April 

2015): 499.

82. Peresin and Cervone, “The Western Muhajirat of 

ISIS,” 499.
32

jihad, like cooking or being nurses for soldiers.”83 But 

living conditions were bleak, and, once the women 

had arrived, leaving was difficult.

Roughly 4 percent of the US émigrés to 

the caliphate—12 individuals—were identified as

minors.84 This percentage does not include any new 

children born in Syria or Iraq to fighter and women 

émigrés from the United States. Still, these numbers 

pale in comparison to the 4,640 minors estimated to 

reside in the caliphate.85 The five categories of children 

residing in the caliphate are

1. those born to foreign fighters;

2. those born to local fighters;

3. those who had been abandoned and found their 

way into ISIS-controlled orphanages;

4. those coercively taken from their parents; and

5. those who voluntarily joined the Islamic State.86

Depending on their location, one can estimate to 

which category children likely belong. For instance, 

“the children in training camps tend to be those 

who have been taken from families or found in 

orphanages,” and children in Islamic State-controlled 

schools “tend to be those whose families volunteered 

them.”87 Emigré minors from the United States 

would likely be part of the first category. As part of 

the grooming process, Islamic State fighters have 

83. Peresin and Cervone, “The Western Muhajirat of 

ISIS,” 499.

84. Cook and Vale, From Daesh to ‘Diaspora’, 20.

85. Cook and Vale, From Daesh to ‘Diaspora’, 14.

86. Mia Bloom, “Cubs of the Caliphate: The Children of 

ISIS,” Foreign Affairs, July 21, 2015, https://www.foreignaffairs

.com/articles/2015-07-21/cubs-caliphate.

87. Bloom, “Cubs of the Caliphate.”
33

encouraged impressionable children to attend public 

executions. Islamic State propaganda videos have 

often shown children “pushing through the rows 

of adults to reach a prime viewing position.”88 Such 

indoctrinated youth become “cubs” and “pearls” of 

the caliphate.

To be considered a cub of the caliphate, male 

minors are subjected to training and conditioning by 

Islamic State standards. At least 2,000 young males are 

believed to have “undergone military training,” which 

included “military and combat skills . . . [and] weapons 

and explosives training . . . and which culminated in the 

execution of prisoners.”89 Physical and psychological 

conditioning is the Islamic State’s way of normalizing 

violence and killings. These cubs are groomed to 

be the future of the Islamic State. This process of 

socialization is said to be composed of a six-stage 

process: seduction, schooling, selection, subjugation, 

specialization, and stationing.90 Currently, children 

of Islamic State fighters are predominantly living in 

Syrian encampments, either orphaned or with their 

mothers, and are still being indoctrinated in Islamic 

State ideology. Girls, known as “pearls,” can marry 

at age nine under Islamic State law. Girls are brought 

up to understand Islamic State ideology, “building the 

Ummah, producing men, and sending them out to the 

fierceness of battle.”91 Although neither noncombatant 

88. Bloom, “Cubs of the Caliphate.”

89. Cook and Vale, From Daesh to ‘Diaspora’, 34.

90. John Horgan et al., “From Cubs to Lions: A Six Stage 

Model of Child Socialization into the Islamic State,” Studies in 

Conflict & Terrorism 40, no. 7 (2017): 11–12.

91. Noman Benotman and Nikita Malik, The Children 

of Islamic State (London: Quilliam, March 2016), 45. See also 

Islamic State, “To Our Sisters: A Jihad without Fighting,” Dabiq, 

September 9, 2015.
34

Islamic State women nor children generally pose a 

direct homeland threat to the United States, they can 

be viewed in many instances as auxiliaries to Islamic 

State fighters, especially the cubs of the caliphate, 

who represent protofighters and are of concern from 

a lateral battlefield transfer perspective. The ability 

of cubs to slip through security checkpoints easily as 

part of refugee groups is a significant concern. Indeed, 

techniques of faking one’s death on social media 

accounts and losing passports and then claiming to be 

someone else are common ploys.92

ISLAMIC STATE STRATEGIC OPTIONS

The Islamic State has four strategic options it could 

presently be pursuing, the last of which represents the 

most viable long-term strategic future for the group.93

The Islamic State has reverted to the previous version 

of itself—the ISI writ large as a global insurgency—by 

developing smaller groups or microcaliphates within 

fertile regions characterized by porous borders, lack 

of political capacity, and high levels of governmental 

corruption. The group’s strategic options are 

explored next.

92. See Anne Speckhard, Adrian Shajkovci, and Ahmet S.

Yala, “Following a Military Defeat of ISIS in Syria and Iraq: 

What Happens Next after the Military Victory and the Return of 

Foreign Fighters,” Journal of Terrorism Research 8, no. 1 (February 

2017): 81–89.

93. Additional outcomes and options exist; these outcomes 

and options are the more probable ones and the most relevant 

to the issue of extremist fighter migration. See Andrew Byers, 

“Postscript: Islamic State Futures,” in Hammer of the Caliphate: 

The Territorial Demise of the Islamic State: A Small Wars Journal 

Anthology, ed. Dave Dilegge and Robert J. Bunker (Bloomington, 

IN: XLIBRIS, April 9, 2018), 443–457.
35

Strategic Option 1

Reestablish the Caliphate: As with any group after 

it suffers major losses, the Islamic State still seeks to 

regain power, which may prove to be an 

insurmountable task. The group has lost a majority 

of the finances it used to sustain itself, including 

revenue from oil fields and taxes, and presently 

cannot expect any windfalls from war booty. But 

the Islamic State has been able to hang on “in part 

because of conflicting priorities among the many local 

and foreign troops fighting in Syria, which includes 

Iranian forces patrolling parts of the Syrian Desert 

and in areas where Russia has conducted airstrikes.”94

Nonetheless, US and coalition forces have successfully 

pushed Islamic State fighters out of both Syria and 

Iraq, and the fighters who remain are not strong 

enough to reestablish the caliphate. In May 2018 

alone, the United States “conducted 225 air strikes 

on Islamic State positions—three times as many as 

in March,” targeting specific positions where pockets 

of fighters were located.95 Given that multiple states 

are inside the conflict zone and air strikes persist, the 

Islamic State territorially reconstituting itself would be 

nearly impossible.

Strategic Option 2

Accept Loss of Territory and Go to Ground: The Islamic

State has not conceded defeat with the loss of the 

caliphate. Maintaining attacks in Iraq and Syria 

94. Sune Engel Rasmussen et al., “ISIS Remnants Fight 

On, Despite US Campaign,” Wall Street Journal, July 9, 2018,

https://www.wsj.com/articles/isis-remnants-fight-on-despite

-u-s-campaign-1531147121.

95. Rasmussen et al., “ISIS Remnants Fight On.”
36

is enough for the group to signal that it is still 

functioning—albeit as a wounded political-religious 

entity. The Islamic State’s smaller groups operating 

across the Middle East, Africa, and Southeast Asia are 

enough to convince the international community the 

group has not necessarily lost territorial influence or 

control in various regions. Furthermore, the Islamic 

State’s online propaganda outlet, the Amaq News 

Agency, continues to operate out of eastern Syria, 

although in a weakened capacity.96 Additionally, the 

Islamic State may still have hidden weapons and other 

munitions in Syria and Iraq that US and coalition 

forces have not yet unearthed. In Iraq, the Islamic 

State maintains a presence through sleeper cells, with 

fighters hiding in the desert regions of Al Anbar; 

the Ghadaf Valley; and al-Hussainiyah, west of Ar 

Rutbah.97 Down to only 2 percent of its former lands 

in Syria and Iraq, the Islamic State has increased hitand-run attacks and suicide bombings as it has shifted 

to a postterritorial reality. Currently, too many armed 

units—backed by devastating airpower and precisionstrike resources—have been deployed by too many 

foes in these areas of operations for Islamic State 

formations to hold ground effectively.

Strategic Option 3

Jihad against the West (and Russia): This strategic 

option could be considered by returnees or individuals 

radicalized at home who have the desire to launch 

attacks from within the Western country in which they 

reside. Individuals who have fought on the SyrianIraqi battlefield and have managed to return home 

96. UN Security Council, Twenty-Second Report, 5.

97. UN Security Council, Twenty-Second Report, 7.
37

successfully without arrest are capable of launching 

internal attacks. For example, Abdelhamid Abaaoud, 

the alleged leader of the November 2015 Paris 

attacks, returned from a visit to Syria and recruited 

a network of radicalized individuals in support of 

this operation.98 Fighters already in Syria and Iraq 

from Western countries are also able to recruit and 

guide others online to “commit attacks in Western 

countries without even returning home.”99 As such, 

multiple homegrown attacks across Europe and even 

the United States have been conducted by individuals 

who have been radicalized online without having 

ever visited the conflict zone. Maintaining the Islamic 

State’s propaganda at some level is necessary to 

continue the proselytization of sympathizers abroad 

who may eventually launch attacks from their home 

countries. Providing homegrown extremists with 

veteran leadership via foreign fighter repatriation 

represents a dangerous combination.

Strategic Option 4

Create Microcaliphates (Global Insurgency): The 

Islamic State appears to be gravitating toward this 

strategic option. This option promotes the creation of 

regional microcaliphates within a global insurgency 

strategy. Such microcaliphates are bound together 

by allegiances between feudal war leaders. The 

organization now represents a shifting hierarchical 

and network-based entity with mixtures of directives 

(direct control) and influence activities (indirect 

control). This global Islamic State strategic approach 

subsumes strategic option 2 (localized insurgency 

98. UN Security Council, Twenty-Second Report, 7.

99. UN Security Council, Twenty-Second Report, 7.
38

focused within Syria and Iraq) and draws upon 

strategic option 3 (jihad in the form of terrorism 

directed against the West) as a supporting substrategy. 

The Islamic State has developed a substantial network 

of affiliate groups outside of Syria and Iraq in parts 

of Africa, Southeast Asia, and Afghanistan. This 

branching out suggests the Islamic State has fully 

readjusted its strategy from territorial state expansion 

and is reverting to its roots as an insurgency, though 

now fully on a macro level. This shift in strategic focus 

is more in line with ongoing al-Qaeda strategies. This 

shift in strategy will likely make al-Qaeda’s strategic 

efforts redundant and may bring the two groups 

closer to one another—though this is unlikely, given 

the animosity between their respective leaderships.

The Islamic State’s weekly newsletter, Al-Naba, 

“hinted at a major change of strategy in a series of 

articles published between September and October 

2017 on the topic of dealing with the US air campaign,” 

and in an October 12, 2017 issue, the group suggested 

it “had again been forced to switch to insurgency 

tactics like in the spring of 2008,” referring to the 

ISI.100 Hit-and-run attacks predominantly in Iraq and 

increased suicide attacks in Syria are indicative of this 

reversion.101 Next is an overview of the geographic 

100. Hassan Hassan, “Insurgents Again: The Islamic State’s 

Calculated Reversion to Attrition in the Syria–Iraq Border Region 

and Beyond,” CTC Sentinel 10, no. 11 (December 2017): 5–6.

101. Hassan, “Insurgents Again,” 6.
39

disposition of these regional microcaliphates and their 

estimated strength (see table 3).102

Table 3. Islamic State global disposition of fighters

Regional Group State(s) Fighters (Estimated)

Islamic State in Iraq 

and Syria (ISIS); 

Postterritorial Caliphate

Syria, Iraq 20,000–30,000 (Both; 

July 2018)

15,500–17,100 (Iraq; 

February 2018)

13,100–14,500 (Syria; 

February 2018)

Islamic State in Sinai; 

Formerly Ansar Beit 

al-Maqdis

Sinai region of Egypt 1,000–1,500 (August 

2018) 

Islamic State West Africa 

Province (ISWAP); Boko 

Haram components

Nigeria (Lake Chad 

area), Chad, Niger, 

Cameroon

3,500 (April 2018) 

Islamic State in the 

Greater Sahara

Mali–Niger Border 

Region

400 (July 2018)

Islamic State of Iraq and 

the Levant in Libya

Libya 3,000–4,000 (July 

2018 est.) 

Islamic State of Iraq 

and the Levant—

Khorasan (IS-K)

Areas of Iran, 

Afghanistan, Pakistan

1,000–2,000 

(Afghanistan; 

December 2017) 

Islamic State in the 

Philippines (IS-P); Abu 

Sayyaf components

Philippines 200 (April 2018 est.)

102. Although other, lesser Islamic State regional groups 

exist—such as those found in East Africa, Saudi Arabia, 

Bangladesh, and Indonesia—they are viewed as not being of 

sufficient strength to be able to presently engage in insurgency 

operations. Since this research has been conducted, some new 

works related to Islamic State foreign fighters and their estimated 

numbers have appeared. These works include Daniel Byman, 

Road Warriors: Foreign Fighters in the Armies of Jihad (Oxford, UK: 

Oxford University Press, 2019); Sam Mullins, Jihadist Infiltration 

of Migrant Flows to Europe: Perpetrators, Modus Operandi and Policy 

Implications (New York: Palgrave Pivot, 2019); and Elena Pokalova, 

Returning Islamist Foreign Fighters: Threats and Challenges to the 

West (New York: Palgrave Macmillan, 2019).
40

Regional Data

Middle East: Iraq, Syria, and Egypt

Since 2014, Combined Joint Task Force-Operation 

Inherent Resolve has worked in conjunction with 

coalition partners to fight the Islamic State threat in 

Syria and Iraq. For the second quarter of 2018, the goal 

of the Operation Inherent Resolve campaign was to 

“prevent ISIS from being able to hold key terrain and 

influence major population centers, field forces that 

can challenge the [Iraqi Security Forces] and coalition, 

build external support networks, or expand influence 

through information operations.”103

According to the August 2018 lead inspector 

general report on Operation Inherent Resolve, violence 

in Iraq declined in all but three provinces: Kirkuk, 

Diyala, and Salah ad Din, all of which experienced 

increased attacks along the “green line” that runs 

along territory claimed by both the central government 

and the Kurdistan Regional Government.104 Reports 

from the UN estimate the number of Islamic State 

fighters to be between 20,000 and 30,000, split almost 

evenly between Iraq and Syria. The August 2018 lead 

inspector general report agreed, estimating between 

15,500 and 17,100 Islamic State fighters remain in 

Iraq.105 The Department of Defense also estimated 

between 13,100 and 14,500 Islamic State fighters are 

in Syria, of which 4,000 to 6,000 remain in the US 

103. Glenn A. Fine, Lead Inspector General Report to the United 

States Congress: Operation Inherent Resolve, Operation Pacific EaglePhilippines: April 1, 2018—June 30, 2018 (Washington, DC: Office 

of Inspector General, DoD, August 6, 2018), 18. 

104. Fine, Operation Pacific Eagle-Philippines, 3.

105. Fine, Operation Pacific Eagle-Philippines, 3.
41

military’s areas of operation in northeastern Syria.106

But US operations against the Islamic State were put 

on hold following the killing of Major General Qassem 

Soleimani, commander of Iran’s Islamic Revolutionary 

Guard Corps Quds Force, on January 2, 2020. Efforts 

transitioned to force protection in anticipation of 

Iranian retaliation. Since the defeat of the physical 

caliphate, the death of Abu Bakr al-Baghdadi, and 

the naming of new leader Abu Ibrahim al-Hashimi 

al-Qurashi, the Islamic State’s capabilities have not 

been significantly degraded.107

In Egypt, the Islamic State in Sinai was previously 

known as “Ansar Beit al-Maqdis,” which began as 

an insurgent group in early 2011 during the Arab 

Spring, shortly after Hosni Mubarak’s overthrow.108

In November 2014, the group changed its name to 

Islamic State in Sinai when its leader’s pledge to Abu 

Bakr al-Baghdadi was accepted within three days. 

The group has launched a series of attacks in the 

region, “most notably claiming credit for the October 

2015 downing of Russian Metrojet Flight 9268, which 

killed all 224 passengers and crew members.”109 The 

Islamic State in Sinai is estimated to have 1,000 to 

1,500 fighters.110

106. Fine, Operation Pacific Eagle-Philippines, 42.

107. Glenn A. Fine, Lead Inspector General Report to the 

United States Congress: Operation Inherent Resolve: October 1, 2019–

December 31, 2019 (Washington, DC: Office of Inspector General, 

DoD, January 31, 2020).

108. Jason Warner and Charlotte Hulme, “The Islamic 

State in Africa: Estimating Fighter Numbers in Cells across the 

Continent,” CTC Sentinel 11, no. 7 (August 2018): 23.

109. Warner and Hulme, “The Islamic State in Africa,” 23.

110. Warner and Hulme, “The Islamic State in Africa,” 23.
42

Africa

Data on Islamic State fighters in Africa is limited. 

Though not overtly engaged militarily in Africa, 

the United States is directly working with partner 

nations to prevent the Islamic State and other jihadist 

cells from forming, as well as pushing against cells 

currently in operation with ongoing drone and other 

surgical strikes.111 In June 2018, Brett McGurk, former 

special presidential envoy to the Global Coalition to 

Defeat ISIS, said the United States and African partner 

states will work as a “coalition to close facilitation 

networks and transit routes running through Libya, 

Sudan, and the Maghreb.”112 McGurk noted Islamic 

State affiliates had “sprung from groups previously 

affiliated with al-Qaeda, and other similar extremist 

organizations.”113 Although the United States is 

working indirectly, Secretary of Defense Mark Esper 

has already cut over 1,000 personnel from United 

111. Special Forces teams have been deployed, and the 

United States is in the process of building a drone base in Nigeria. 

See Eric Schmitt, “A Shadowy War’s Newest Front: A Drone 

Base Rising from Saharan Dust,” New York Times, April 22, 2018, 

https://www.nytimes.com/2018/04/22/us/politics/drone

-base-niger.html.

112. Brett McGurk, “Remarks at the Political Director’s 

Meeting of the Global Coalition to Defeat ISIS” (speech, Political 

Director’s Meeting of the Global Coalition to Defeat ISIS, Skhirat, 

Morocco, June 26, 2018), https://www.state.gov/remarks-at-the

-political-directors-meeting-of-the-global-coalition-to-defeat

-isis-2/.

113. McGurk, “Remarks at the Political Director’s Meeting.”
43

States Africa Command posts, leaving about 6,000 

troops and civilians in Niger, Somalia, and Djibouti.114

The most notable group affiliated with the Islamic 

State is Boko Haram. In March 2015, Boko Haram’s 

leader, Abubakar Shekau, pledged allegiance to the 

Islamic State, which acknowledged the pledge a few 

days later. This new group became known as the 

Islamic State West Africa Province (ISWAP), which 

operates in the Chad Basin region. But tensions 

flared between the two groups by August 2016 over 

ISWAP’s leadership.115 Shekau was replaced with Abu 

Musab al-Barnawi, the son of Muhammed Yusuf, the 

founder of Boko Haram. Barnawi is the current leader 

of ISWAP, and Boko Haram officially rebranded as 

ISWAP during the transition.116 In April 2018, the DoD 

estimated ISWAP consisted of about 3,500 fighters, and 

the group is believed to be the largest affiliate in terms 

of fighters and territory, operating in the Lake Chad 

region of Nigeria, Chad, Niger, and Cameroon.117

The Islamic State Algeria Province started strongly 

but quickly collapsed. The group was formed in 

September 2014 by Abdelmalek Gouri, a former highranking al-Qaeda in the Islamic Maghrib member. 

The Islamic State Algeria Province became known 

114. Michael M. Phillips, “US Weighs Troop Cuts in Africa, 

Leaving Allies to Confront Growing Militant Threat,” Wall Street 

Journal, March 15, 2020, https://www.wsj.com/articles/u-s

-weighs-troop-cuts-in-africa-leaving-allies-to-confront-growing

-militant-threat-11584291493.

115. Warner and Hulme, “The Islamic State in Africa,” 22.

116. Warner and Hulme, “The Islamic State in Africa,” 22.

117. Christopher M. Blanchard and Carla E. Humud, 

The Islamic State and U.S. Policy, R43612 (Washington, DC: 

Congressional Research Service, September 25, 2018), 18, https://

fas.org/sgp/crs/mideast/R43612.pdf; and McGurk, “Remarks at 

the Political Director’s Meeting.”
44

internationally after it kidnapped and beheaded 

French hiker Hervé Gourdel as retribution for French 

air strikes in Iraq.118 But Gouri had been killed by the 

end of 2015, and the majority of the group’s members 

were soon either arrested or killed.119 The Islamic State 

Algeria Province was successful in recruiting al-Qaeda 

in the Islamic Maghrib members and has launched 

attacks in Jijel, Constantine, Tiaret, and the outskirts 

of Algiers, Skikda, and Annaba. But the group is no 

longer believed to be much of a threat, with strength 

estimates of less than 25 fighters.120

The Islamic State in the Greater Sahara, led by 

Adnan Abu Walid al-Sahraoui, formed in May 2015. 

Sahraoui was a senior al-Qaeda affiliate leader, but 

his pledge to the Islamic State was not acknowledged 

until October 2016. The group operates on the border 

between Mali and Niger and is known primarily for its 

October 2017 attack in Tongo Tongo that claimed the 

lives of four US servicemembers and five Nigerians. 

As of July 2018, the Islamic State in the Greater Sahara 

was estimated to have a little over 400 fighters.121

Libya continues to struggle with the remnants 

of the Islamic State. Islamic State cells first emerged 

in Darnah in April 2014 “when a band of just 300 

fighters—many of whom had returned from fighting 

in Syria—returned to Libya and allied with members 

118. Warner and Hulme, “The Islamic State in Africa,” 22.

119. International Crisis Group, How the Islamic State Rose, 

Fell, and Could Rise Again in the Maghreb, Middle East and North 

Africa Report no. 178 (Brussels: International Crisis Group, July 

24, 2017), 22.

120. Warner and Hulme, “The Islamic State in Africa,” 22.

121. UN Security Council, Twenty-Second Report, 24.
45

of pre-existing jihadi groups.”122 The Islamic State of 

Iraq and the Levant in Libya was officially recognized 

in November 2014, and three branches were 

established in the Libyan regions Cyrenaica, Fezzan, 

and Tripolitania, with a total of about 500 fighters.123

By June 2015, the group had lost Darnah to al-Qaeda 

affiliates, but the group subsequently gained the city of 

Sirte. In mid-2016, the CIA estimated the Libya branch 

had between 5,000 and 8,000 fighters.124 Currently, the 

Islamic State has somewhat of a presence in Libya, 

“abetted by the fluid security situation, some tribal 

support and coordination with other terrorist groups 

when expedient.”125 Specifically, cells are controlled 

around “Tripoli, Misrata and Sabratah in the west, 

with a substantial presence in southern Libya around 

Ghat and Al Uwainat, and Ajdabiya and Darnah in 

the east.”126 The group is still able to launch attacks 

from the country with asymmetric tactics and the use 

of improvised explosive devices. Present estimates 

range between 3,000 and 4,000 fighters across Libya, 

with the group’s central command located in the 

122. UN Security Council, Twenty-Second Report, 23–24. 

See also Hasan Morajea and Erin Cunningham, “Libyan Gains 

May Offer ISIS a Base for New Attacks,” Washington Post, June 

6, 2015, https://www.washingtonpost.com/world/middle_east

/in-libyas-civil-war-the-islamic-state-shows-itself-as-the-main

-threat/2015/06/06/65766592-0879-11e5-951e-8e15090d64ae

_story.html.

123. UN Security Council, Twenty-Second Report, 23–24.

124. Julian Hattem, “CIA: Undaunted ISIS is Expanding, 

Focused on Attacking West,” Hill, June 16, 2016, https://thehill.

com/policy/national-security/283763-cia-says-undaunted-isisis-expanding-focused-on-attacking-west.

125. UN Security Council, Twenty-Second Report, 7.

126. UN Security Council, Twenty-Second Report, 7.
46

“triangle between Bani Walid, southern Sirte and 

Jufrah district.”127

Afghanistan

The Islamic State established a group in Khorasan 

Province, the Islamic State of Iraq and the LevantKhorasan (IS-K), which covers parts of Iran, 

Afghanistan, and Pakistan. Formally established on 

January 10, 2015, IS-K became the target of the Afghan 

Taliban as a competing jihadist group. Experts credit 

the group’s development to defections from smaller 

groups across Afghanistan and Pakistan. The group’s 

numbers increased as fighters fled Syria and Iraq and 

some Afghan Taliban defectors joined. In addition, 

some fighters from other militant groups, such as 

Pakistan’s al-Qaeda-aligned Tehreek-e-Khilafat and 

Tehrik-i-Taliban Pakistan, also joined.

The Islamic State enhanced its propaganda efforts 

in Khorasan Province, particularly from Kabul to 

Jalalabad and Peshawar. Afghanistan’s Nangarhar 

Province had the greatest number of battles between 

IS-K and the Afghan Taliban. The group claimed 

multiple districts in which it had forced the Taliban to 

retreat. The Islamic State affiliate has largely been an 

intrusion and has impeded the Taliban’s effort to attack 

US and Afghan forces. These actions have represented 

a double-edged sword for the United States because 

the Taliban represents a direct threat to governance in 

Afghanistan, and the Islamic State is a greater global 

concern. Current estimates indicate between 1,000 

and 2,000 Islamic State fighters are in Afghanistan and 

are continuing campaigns to further expand into the 

northeastern part of the country, where the group is 

127. UN Security Council, Twenty-Second Report, 10.
47

currently active in the Jowzjan and Sar-e Pul Provinces 

and Kandahar.128 The fighter estimates for IS-K are 

rather small compared to estimates of the Islamic 

State’s presence in Syria and Iraq, but IS-K is a prime 

example of the Islamic State successfully carrying out 

attacks and preserving its brand.

Southeast Asia

Southeast Asia has no official Islamic State 

branch or province, but multiple attacks have 

occurred across the region since 2014, most notably 

the 2017 Marawi siege (also known as the Battle 

of Marawi) in the Philippines. A 2017 Combating 

Terrorism Center report stated Islamic State attacks 

in the region occurred “primarily in Malaysia (41%), 

Indonesia (36%), the Philippines (17%), and Singapore 

(6%),” with the majority of attacks occurring in the 

Philippines (50 percent) and Indonesia (45 percent).129

The most recognizable Islamic State affiliate in the 

region is the Islamic State in the Philippines (IS-P), 

established in July 2014. Officials from the Department 

of Defense, however, believe the IS-P is weak because 

of its poor command and control and a lack of funding 

from ISIS, which has been unable to support the group 

since October 2017.130 Nonetheless, the Marawi siege 

left a significant number of individuals displaced, and 

sympathizers could potentially develop sleeper cells. 

128. Kenneth Katzman and Clayton Thomas, Afghanistan: 

Post-Taliban Governance, Security, and US Policy, RL 30588 

(Washington, DC: Congressional Research Service, December 13, 

2017), 20.

129. Marielle Ness, “Beyond the Caliphate: Islamic State 

Activity outside the Group’s Defined Wilayat (Southeast Asia),” 

CTC Sentinel 10, no. 6 (June/July 2017): 2–3.

130. Ness, “Beyond the Caliphate,” 14.
48

United States Indo-Pacific Command officials estimate 

the IS-P’s total force strength is approximately 200 

fighters from different radical Islamist factions.131

Analysis

Although some extremist fighters have managed 

to return to their countries of origin, others will 

remain, which is likely because of their inability to flee 

Syria or Iraq. A third category is the lateral transfer 

of foreign fighters to other battlefields; however, no 

hard data exists concerning such transfers. The overall 

concern is returnees have some combat experience, 

which they may use to commit acts of terrorism if they 

reach home. Returnees who serve as influencers can 

recruit others to launch attacks at home and radicalize 

more potential members. For instance, nine EU states 

reported a total of 205 foiled, failed, and completed 

terrorist attacks in 2017.132 The United Kingdom 

experienced the highest number of incidents—either 

foiled, failed, or completed—at 107, followed by 54 in 

France, 16 in Spain, and 14 in Italy.133 Although jihadibased attacks only represented a fraction of these 

incidents, these types of attacks more than doubled 

from 2016 to 2017, and they tended to have more 

media impact.

The number of women and children returnees is 

even more difficult to estimate, especially because of 

the uncertainty of the nationality of children born in 

the conflict zone. Many children were also exposed to 

extreme violence and may even have been involved 

in the fighting as cubs of the caliphate, making them 

131. Fine, Operation Pacific Eagle-Philippines, 108.

132. EUROPOL, TE-SAT 2018, 9.

133. EUROPOL, TE-SAT 2018, 9.
49

more dangerous. The involvement of children further 

complicates the manner in which states will process 

their returnees, or whether states will even consider 

taking the returnees back.

Multiple countries have prevented foreign 

fighters from returning home, limiting the spread of 

fighters and the establishment of cells. For example, 

Morocco has well-guarded borders—particularly in 

the Western Sahara—and has deployed military and 

law enforcement since 2014 to locations the country 

believes could potentially be vulnerable.134 Algeria 

has also been successful staying ahead of the Islamic 

State threat with the use of military and other security 

enforcements, including cybersecurity. In other 

countries, US and coalition forces help by providing 

continued air strikes or by assisting a state’s forces. 

According to the latest numbers released by the 

US military under Operation Inherent Resolve, the 

coalition has conducted 24,566 air strikes across the 

conflict zone to degrade the Islamic State and flush out 

remaining fighters.135

Other forms of assistance include designating 

groups as foreign terrorist organizations, which helps 

other countries target the Islamic State. The IS-P 

has been unable to regain strength since 2017.136 In 

February 2018, the US Department of State designated 

the IS-P as a foreign terrorist organization, followed 

by a US Department of the Treasury sanction against 

an IS-P financier in April 2018. Moreover, the United 

134. International Crisis Group, How the Islamic State Rose, 24.

135. Brian Dodwell, Daniel Milton, and Muhammad 

Al-`Ubaydi, “Burying the Lede: The Islamic State Downsizes?,” 

Combating Terrorism Center at West Point (website), July 20, 2018, 

https://ctc.usma.edu/burying-lede-islamic-state-downsizes/.

136. Fine, Operation Pacific Eagle-Philippines, 46.
50

States’ overseas contingency operation, known as 

Operation Pacific Eagle-Philippines, supports the 

Armed Forces of the Philippines in fighting Islamic 

State sympathizers and the IS-P in the country. Since 

September 2017, Operation Pacific Eagle-Philippines 

has been supporting “the Philippine government and 

military in their efforts to isolate, degrade, and defeat 

ISIS affiliates and other terrorist organizations in 

the Philippines.”137

In certain parts of Africa and the Middle East, the 

Islamic State is maintaining its operational tempo; 

this return to insurgency tactics is a viable means of 

establishing smaller groups in vulnerable areas. See 

table 4 for continued attacks by the Islamic State as of 

July 2018.138

137. Fine, Operation Pacific Eagle-Philippines, 102.

138. All country information in table 4 is from “Crisis Watch: 

July 2018,” International Crisis Group, https://www.crisisgroup

.org/crisiswatch/july-2018. A note on Boko Haram: Whether the 

attacks were perpetrated by the pro-Barnawi faction (ISWAP) or 

the pro-Shekau faction, which continues to support Islamic State 

Central, is uncertain.
51

Table 4. Continued attacks by Islamic State 

as of July 2018

Country Situation as of July 2018

Libya The Islamic State and other armed groups continue attacks 

on civilians, especially in southern Libya. The Islamic State 

weekly newspaper, Al-Naba, reported on July 6, 2018, the 

Islamic State captured two air force officers in the Fezzan 

region. On July 7, 2018, at a Tazirbu water plant, suspected 

militants killed two workers and kidnapped two others. 

Islamic State affiliates killed two policemen in Al ‘Uqaylah 

on July 24, 2018.

Egypt Islamic State attacks continue in the Sinai Peninsula, even 

as two Islamic State commanders reportedly surrendered 

to security forces in Rafah in early July 2018. On July 3, 

2018, the military stated three suspected Islamic State 

militants had been killed in North Sinai. On July 11, 2018, 

forces killed 11 Islamic State militants during a raid in Al 

‘Arish and 13 others on July 24, 2018. 

Chad Boko Haram militants attacked a village near the Niger 

border on July 19, 2018, killing 18 and kidnapping 

10 women.

Niger Suspected Boko Haram militants continue attacks in 

the Diffa region in the southeast. The militants attacked 

a military position on July 1, 2018, in Bla Brin village in 

the Lake Chad area, killing six soldiers. Militants attacked 

another military post in Baroua village on July 19–20, 2018, 

near the Nigerian border.

Nigeria Islamic State West Africa Province Boko Haram continued 

attacks on military and civilians in Borno, Yobe, and 

Adamawa states. In Borno, militants ambushed an army 

convoy near Bama on July 13, 2018. Militants killed six 

traders at Mussini village on July 17, 2018; at least 27 near 

Gajibo village on July 18, 2018; at least 7 in a suicide attack 

at a Konduga mosque on July 23, 2018; and at least 13 in 

an attack on military in Jakana on July 26, 2018. In Yobe, 

militants attacked a military base in Jilli on July 14, 2018. 

In Adamawa, militants killed five civilians in Luru on July 

10, 2018.

Iraq Islamic State attacks continue in Kirkuk, Diyala, and Salah 

ad Din Provinces.

Syria Islamic State militants continue to carry out suicide 

bombings. Multiple suicide bombings were reported on 

July 25, 2018, in government-held As-Suwayda city and 

against progovernment forces and civilians in nearby 

villages, killing at least 200.
52

The future migration potential of fighters is 

difficult to assess. Estimates could include fighters, 

family members of deceased fighters, or sympathizers 

who have little to no combat experience.139 According 

to the 2018 lead inspector general report, the Islamic 

State “has not yet identified as an insurgency but 

rather continued to see itself as a state with a standing 

army.”140 The Islamic State is conserving forces “for an 

insurgency that the Department of Defense predicted 

would stretch across the desert in eastern Syria and 

western Iraq, terrain that is well suited as a base for 

guerilla warfare.”141 The group will have to “rely on 

rural and desert insurgency in addition to urban 

warfare to recruit members and ‘lay the groundwork 

for a comeback.’”142 As of mid-2018, the Islamic State 

has control of little territory in Syria; that which the 

group does control is concentrated in “eastern Syria, 

the Middle Euphrates River Valley, and rural areas 

of southern Hasakah Province, as well as a third 

pocket in the Yarmuk Basin in Dar’a Province south 

of Damascus.”143 As General Joseph F. Dunford stated 

in October 2017, the Islamic State is trying to “leverage 

local insurgencies now to rebrand themselves” and to 

maintain relevance.144 The Islamic State is achieving 

this effect in places like Libya, Egypt’s Sinai Peninsula, 

139. Jeff Seldin, “Far from Dead: Tens of Thousands 

of IS Fighters Linger in Iraq, Syria.” VOA News, August 

13, 2018, https://www.voanews.com/a/far-from-dead-tens-of

-thousands-of-is-fighters-linger-in-iraq-syria/4527452.html.

140. Fine, Operation Pacific Eagle-Philippines, 46.

141. Fine, Operation Pacific Eagle-Philippines, 46.

142. Fine, Operation Pacific Eagle-Philippines, 46.

143. Fine, Operation Pacific Eagle-Philippines, 45–46.

144. Joseph F. Dunford Jr., “CHOD Conference Press 

Briefing” (speech, Chiefs of Defense Conference, Fort Belvoir, VA, 

October 24, 2017).
53

and other parts of Africa. Migration patterns are 

indicative of Islamic State fighters dispersing to areas 

in which they can operate more freely, but the patterns 

do not indicate a large number of fighters has flowed 

out of Iraq and Syria.145

COUNTERBATTLEFIELD MIGRATION 

POLICY RESPONSE

Battlefield migration response policies necessitate 

that the foreign fighter threat be placed in context. The 

datasets highlighted in the demographic overview 

have a great degree of uncertainty because of the 

use of different methodologies and both official and 

unofficial statements. For instance, in 2015, the thendirector of the National Counterterrorism Center, 

Nicholas Rasmussen, stated “more than 20,000 foreign 

fighters” have traveled to Syria “from over 90 different 

countries,” and “at least 3,400 of these fighters are 

from Western countries.”146 In June 2016, then-director 

of the CIA John Brennan told the Senate Intelligence 

Committee in a rare public hearing the total Islamic 

State fighting force was between 18,000 and 22,000, 

which is lower than it was in 2015, when it had as 

many as 33,000.147 The estimate of confirmed Islamic 

State deaths further complicates the interpretation of 

the available data. In July 2017, then-commander of 

United States Special Operations Command General 

145. Dunford, “CHOD Conference Press Briefing.”

146. Countering Violent Islamist Extremism (statement of 

Rasmussen).

147. Patricia Zengerle and Jonathan Landay, “CIA 

Director Says Islamic State Still Serious Threat,” Reuters, June 

16, 2018, https://www.reuters.com/article/us-mideast-crisis

-fighters/cia-director-says-islamic-state-still-serious-threat

-idUSKCN0Z21ST.
54

Raymond Thomas stated at a security forum, in 

reference to the US and coalition forces, “we have killed 

in conservative estimates 60,000 to 70,000 of [Abu Bakr 

al-Baghdadi’s] followers.”148 Assuming the estimate 

is accurate and includes kills that have occurred since 

the establishment of the caliphate in 2014, the number 

of total Islamic State fighters is potentially higher than 

the numbers that have been reported because the CIA 

indicated up to 22,000 fighters had left by June 2016. 

July and August 2018 reports by the UN and the lead 

inspector general, respectively, claim the number of 

Islamic State fighters has remained somewhat similar 

to the numbers presented in previous reports—which 

presumably also include foreign fighters.

 Some of the specific issues related to the 

discrepancies, gaps, and inconsistencies inherent in 

these datasets and estimates are the following.

• The July 2017 figure of 60,000–70,000 Islamic 

State fighters killed is potentially more than 

twice the total estimated Islamic State fighting 

force at its 2015 height of 33,000.149

• The Islamic State had lost 98 percent of the territorial caliphate by the spring of 2018, but is 

estimated to have 20,000–30,000 (possibly even 

31,100) members, which is roughly 60 percent 

148. Raymond A. Thomas, “SOCOM: Policing the World,” 

Aspen Security Forum 2017, July 21, 2017, transcript, https://

aspensecurityforum.org/wp-content/uploads/2017/07

/SOCOM_Policing-the-World.pdf.

149. Thomas, “SOCOM: Policing the World”; and Zengerle 

and Landay, “CIA Director Says.”
55

to 94 percent of the estimated 2015 force during 

its height.150

• Foreign terrorist fighters (FTFs) estimated 

to have traveled to the caliphate range from 

27,000–31,000, and possibly up to 41,490.151 Even 

when the estimated 7,366 fighters and familial members who have returned to their countries of origin are factored in, 19,646 to 34,136 of 

the estimated 2015 force equivalence of 33,000 

are foreign fighters.152 These figures suggest 

between 0 and 13,354 Islamic State fighters come 

from Syria and Iraq, though the numbers do not 

factor in post-2015 Islamic State fighter attrition 

rates vis-à-vis later inflows. The zero amount 

is of course an impossibility, showing the wide 

inconsistencies in the estimates that exist when 

checked against one another in an attempt to 

understand the larger extremist fighter dynamics taking place.

• No reliable data or estimates exist of the numbers of Islamic State fighters recruited internally 

from Syria and Iraq.

• No reliable data or estimates exist of lateral 

battlefield migration by Islamic State extremist 

fighters from the Syrian-Iraqi battlefield.

150. Islamic State membership in this estimate is only 

partially fighter-based—the percentages of fighters and 

nonfighters are not specified. Counter-Terrorism Committee 

Executive Directorate, Returning and Relocating Foreign Terrorist 

Fighters, 2; UN Security Council, “Letter Dated 16 July 2018”; Fine, 

Operation Pacific Eagle-Philippines, 3, 9; and Zengerle and Landay, 

“CIA Director Says.”

151. The Soufan Group, Foreign Fighters, 3; and Cook and 

Vale, From Daesh to ‘Diaspora’, 14.

152. Cook and Vale, From Daesh to ‘Diaspora’, 15; and 

Zengerle and Landay, “CIA Director Says.”
56

These issues suggest policy responses related to 

counterbattlefield migration are presently decoupled 

from many of the extremist fighter demographic 

estimates. Although certain datasets and estimates 

may be accurate, the ones that are accurate and the 

ones that are not are unknown.

The Extremist Fighter Threat in Context

Three conditionals exist that allow us to better 

place the extremist fighter and familial-member threat 

in the context of core US security interests. These 

conditionals are the type of extremists of concern, 

their commitment to the cause of the Islamic State, and 

their geographical location. These conditionals and the 

severity of the threat—indicated using a color system 

in which red means “dangerous,” yellow means 

“increased warning,” and green means “baseline 

concern”—are representative of the underlying 

potential for violent extremist action to take place.153

The conditionals and severities are as follows.

153. Issues of nonviolent extremism are also of great 

importance, but they remain subordinate to concerns related 

to violent extremism. Still, issues of nonviolent extremism are 

being increasingly addressed and even viewed in some instances 

as precursors to violent extremism. For background on initial 

perceptions related to nonviolent extremism thinking and public 

policy focused on radical Islamists in the United Kingdom, see 

Theresa May, Counter-Extremism Strategy, Command Paper 9148 

(London: Home Office, October 2015); and Theresa May, Forward, 

Together: The Conservative and Unionist Party Manifesto 2017

(London: The Conservative and Unionist Party, 2017), quoted in 

Daniel Kirkpatrick, “Why Criminalising Non-violent Extremism 

Won’t Prevent Terrorism,” The Conversation, June 13, 2017, 

https://theconversation.com/why-criminalising-non-violent

-extremism-wont-prevent-terrorism-78973.
57

• Extremist Type: Islamic State personnel residing 

in Syria and Iraq can be categorized primarily 

within three categories: fighters (who are primarily adult males), cubs, and wives and other 

women who are of childbearing age. Fighters 

are considered dangerous (red), cubs exist at 

the warning level (yellow), and wives are considered benign (green) from a violent extremist perspective. As a note, not all adult males 

are fighters. The Islamic State—like any large 

terrorist or insurgent organization—requires 

administrative personnel to properly function. 

Fighters engage in violent extremism while 

these other personnel—including most fighter 

wives—facilitate violent extremism, rather than 

actually engaging in it. These support personnel and leaders, however, cannot be considered 

as solely engaging in nonviolent extremism 

because they are accomplices to and managers of 

violent extremism. A description of the personnel’s characteristics with caveats can be viewed 

in table 5.154 The conclusions shown in the table 

are from a combat and violence perspective. 

Exceptions exist where women are armed or 

engage in suicide bombings because approximately one in nine women who migrated to join 

the caliphate may be classified as Islamic State 

fighters. But, more often, women engage in 

propaganda, recruitment, indoctrination, and 

materiel-support activities.

• Commitment: Extremist fighters and their family 

members over time have varying levels of commitment to the Islamic State cause. The most 

severe level, red, is reserved for those who are 

154. Adapted from Meines et al., RAN Manual, 6.
58

considered operational in nature. These personnel actively engage in terrorist and insurgent 

activities, which makes them the most dangerous in their commitment levels. The yellow 

level in the commitment scale is composed of 

individuals who have disengaged from jihad 

and become inactive. Within this zone are foreign fighters who have returned home to seek 

better living conditions for themselves and 

their families after having been subjected to the 

deprivations of living in Syria and Iraq.155 These 

extremists continue to support Islamic State 

tenants and represent potential sleeper units if 

allowed to migrate back to the West. So, these 

extremists are still of concern because they 

remain radicalized and may at some point reengage in Islamic State activities. The green level 

of commitment pertains to extremists who have 

become disillusioned with or even remorseful 

about the ideologies and policies of the Islamic 

State and have begun the process of, or are at 

least receptive to, deradicalization. These individuals have essentially sidelined themselves 

from the war the Islamic State is waging, and, 

for this reason, are considered at the baseline 

concern level or potentially lower. These personnel may even prove to be useful tools in the 

deradicalization of others.

• Location: Extremist fighters remaining within 

the Syrian and Iraqi battlefields represent the 

present baseline for US and Western allied security interests and are considered a lesser threat 

to the US homeland. The fighters and their families who have laterally shifted battlefields—as 

155. Meines et al., RAN Manual, 7.
59

long as they do not enter American, European, 

and other Western homelands—are categorized 

at a warning level of concern. Finally, fighters 

and their affiliates who have returned to the 

United States or other Western country of origin 

or who have infiltrated these countries exist at 

the most dangerous threat level because, at a 

minimum, terrorist attack potential now exists.

Synthesizing these three factors—extremist type, 

commitment, and location—provides a continuum of 

threats, from the severe (red) to the baseline warning 

(green), with a sequence of blended combinations 

residing in the middle of this continuum (see table 6).

Table 5. Foreign fighter and familial extremists

Fighters 

(Primarily Males)

Cubs (Young Males) Wives (Females)

• High risk 

of combat 

experience and 

skills

• Often involved 

in and exposed 

to war atrocities

• Variety of roles 

within the 

terrorist-held 

territories 

• Intense ideological 

indoctrination 

through education 

and socialization

• Recruited for combat 

and other violent 

activities from age 

nine

• Severely traumatized 

• Family role and 

mother to future 

soldiers

• Driven by sense 

of empowerment 

and their role 

in building the 

caliphate

• Involved in the 

recruitment and 

indoctrination of 

children and others

Combatants Quasicombatants Noncombatants

Red (dangerous) Yellow (warning) Green (concern)

Though outside the scope of this research, the 

middle-range, blended combinations—such as 

cubs (yellow), operational (red), lateral battlefields 

(yellow)—may provide modeling preference utility 
60

for global counter-FTF activities related to recent 

UN Security Council resolution 2395 (2017) and 

Organization for Security and Co-operation in Europe 

reverse-flow focuses.156

Table 6. Foreign fighter and familial extremist 

threat continuum

Fighters (red)

Operational (red)

US-Western battlefields (red)

Severe threat 

Wives (green)

Disillusioned (green)

Iraq-Syria battlefields (green)

Baseline threat

156. The programs focused on foreign terrorist fighters 

(FTFs) build upon UN Security Council resolution 2178 

(2014), which criminalizes FTF-related activities in all states 

acceding to the resolution. Rex Tillerson, “On the Adoption 

of UN Security Council Resolution 2396 on Foreign Terrorist 

Fighters” (speech, US Department of State, Washington, 

DC, December 21, 2017); Organization for Security and 

Co-operation in Europe, “2018 OSCE-Wide Counter-Terrorism 

Conference: The Reverse Flow of Foreign Terrorist Fighters 

(FTFs): Challenges for OSCE Area and Beyond” (white paper, 

Organization for Security and Co-operation in Europe, May 

10–11, 2018); and Matteo Pugliese, “The OSCE Counter-Terrorism 

Conference: The Reverse Flow of Foreign Terrorist Fighters,” 

June 12, 2018, https://eeradicalization.com/the-osce-counte

-terrorism-conference-the-reverse-flow-of-foreign-terrorist

-fighters/. For background, see “Foreign Terrorist Fighters,” 

UN, https://www.un.org/sc/ctc/focus-areas/foreign-terrorist

-fighters/; UN Security Council, Resolution 2395, Threats to 

International Peace and Security Caused by Terrorist Acts—CTED 

Mandate Renewal, S/RES/2395 (December 21, 2017), https://

undocs.org/en/S/RES/2395%20%282017%29; and UN Security 

Council, Resolution 2396, Threats to International Peace and 

Security Caused by Terrorist Acts—Foreign Terrorist Fighters, 

S/RES/2396 (December 21, 2017), https://undocs.org/en/S

/RES/2396(2017).
61

Policy Response

Derived from the above threat context, the 

counterextremist migration policy response should 

first and foremost focus on the male fighters, and 

then be scalable enough to also include their cubs, 

and then their wives. Early pubescent females—

pearls—have no combat training regime equivalent 

to the cubs of the caliphate. At best, pearls undergo 

Islamic State indoctrination and, over time, have 

had increasing commitment levels. This relative lack 

of commitment means pearls should be considered 

less of a threat than wives (who generally function 

as noncombatants/support personnel) and placed 

with very young (pre-cub) males, (pre-pearl) females, 

and infants, all of whom exist in a protected category 

under international law.

Though conditional variations will of course 

exist, such as operational (red) cubs (yellow) being 

considered more dangerous than disillusioned (green) 

fighters (red), these classifications are not necessarily 

a priori in nature, nor can they be easily determined 

from observation alone.

Additionally, in formulating counterextremist 

migration policies, two levels of targeting should 

be undertaken: one applied toward the extremists 

themselves and the other applied against the Islamic 

State organization’s command and control and 

network influence capabilities. As a component of 

these policies, their potential for second-order effects 

needs to be considered. The policy responses proposed 

need to be weighed against the broader context of US 

foreign policies focused on Syria and Iraq and UN 

programs meant to globally address contemporary 

FTF flows, as well as recommendations related to more 
62

strategically focused US Joint Force considerations. 

The countermigration policies proposed as well as 

their broader US and UN policy interfaces and impacts 

are reviewed next.

Extremist-Focused Response Policies

These response policies should be considered 

additive in nature. The policies are intended to 

complement each other, with each policy meant to 

facilitate the elimination of a threat component of 

the demographic set of extremist fighters and their 

families. In a sense, the policies follow a “render safe” 

approach to mitigating the foreign fighter threat by 

using elimination, containment, and related end states 

to ensure Islamic State personnel remain in the Syrian 

and Iraqi theater of conflict—or, if they eventually are 

able to migrate, have been deradicalized before they 

do so. These policy responses are as follows.

• Target and Kill in Place: This response is the 

currently preferred Western policy and is specifically focused on foreign fighters who are 

active combatants. Armed cubs and wives (as 

well as single females) who possess deadly force 

capabilities are also legitimate targets within 

these rules-of-engagement protocols. Attacks 

using precision-airdropped munitions, missile 

strikes, and artillery fires are dominant means 

of attack, but close-combat operations can and 
63

do take place.157 Well over 20,000 close-combat 

attacks (defined as strikes and engagements) 

have taken place in Syria and Iraq over the last 

few years as Western coalition forces have targeted and destroyed Islamic State forces.158 Second-order effects: Fighters killed in battle achieve 

martyrdom within the radical Islamist mythos, 

and are thus considered by Allah as worthy 

of the highest blessings of paradise. Although 

small numbers of martyrs created within a radical Islamist organization provide morale benefits, large-scale fighter elimination likely has 

the opposite effect. The danger of this form of 

targeting is the collateral damage stemming 

from indiscriminate attacks and resulting in 

the injury and deaths of innocent bystanders. 

Though one enemy may be killed, many other 

new enemies are potentially created from the 

families of those mistakenly targeted.

• Capture of Surrendering Personnel and 

Hors de Combat: Islamic State personnel who 

have surrendered to US and coalition forces 

or who have been captured after being rendered incapable of armed resistance (hors de 

combat) are representative of another policy 

157. As mentioned earlier, an even more precise targeting 

schema has been adopted by the French government. See Tamer 

El-Ghobashy, Maria Abi-Habib, and Benoit Faucon, “France’s 

Special Forces Hunt French Militants Fighting for Islamic State,” 

Wall Street Journal, May 29, 2017, https://www.wsj.com/articles

/frances-special-forces-hunt-french-militants-fighting-for

-islamic-state-1496090116.

158. An analysis of these attacks during a three-month 

period at the end of 2017—October through December—can 

be found in Matt Begert, “CENTCOM Targeting of the Islamic 

State,” in Hammer of the Caliphate, xxvii–xxxii.
64

approach. A recent report from July 2018 states 

US-allied Syrian Democratic Forces have 

detained almost 600 FTFs.159 Jihadi wives and 

cubs are also frequently captured in both Syria 

and Iraq. Second-order effects: Unlike the closure 

brought about by killing Islamic State fighters, 

this policy approach is viewed as transitory 

in nature—such captured enemy combatants 

cannot remain prisoners indefinitely. Indeed, a 

Guantánamo Bay–type detention facility, where 

terrorist detainees are held in an ongoing state of 

legal limbo, would not be politically feasible for 

the United States to establish in Syria or Iraq—

nor should it be considered. Imprisonment 

is a waypoint to trial and sentencing, which 

results in acquittal, prison sentencing, execution, or repatriation into the hands of security 

and police services in the individual’s country 

of origin. Many of these Islamic State detainees 

have been deprived of their citizenship and rendered stateless and are thus banned from being 

repatriated to their countries of origin or to the 

countries in which they had been residing.

• Deradicalize Fighters and Their Families: 

Foreign Islamic State members who have been 

159. These fighters are from over 40 countries, with about 

40 fighters from Russia and about a dozen from Germany and 

France. Ryan Browne, “US-Backed Syrians Holding Nearly 

600 Foreign Fighters,” CNN, July 18, 2018, https://www.cnn

.com/2018/07/18/politics/syrian-allies-foreign-terrorists

/index.html. Total Islamic State fighter detainees may be as high 

as 1,000 in Syria and 10,000 in Iraq. See UN Security Council, 

Seventh Report of the Secretary-General on the Threat Posed by ISIL 

(Da’esh) to International Peace and Security and the Range of United 

Nations Efforts in Support of Member States in Countering the Threat, 

S/2018/770 (New York: UN Security Council, August 16, 2018), 3.
65

detained after being captured or sentenced 

and imprisoned represent fixed audiences that 

can be targeted for deradicalization. Different 

deradicalization protocols and approaches will 

be required for interfacing with fighters, their 

wives, and their cubs. Consideration should 

also be given to focusing psychological operations on remaining Islamic State field force remnants—similarly representing fixed audiences 

because they reside in geographically limited 

enclaves—to begin the deradicalization process 

or induce them to surrender. Besides neutralizing the threat of extremists engaging in violence, some former Islamic State personnel who 

are more secular in their ideological leanings, 

such as former Saddam Hussein regime officers, 

may be induced to become collaborators against 

their former comrades-in-arms by means of 

payments or other inducements. The deradicalization of fully indoctrinated Salafi-jihadists—

Islamic State true believers and apocalyptic 

cultists—is a long and involved process and 

may not be achievable in many instances. For 

example, deprogrammers who are deradicalizing Salafi-jihadists cannot exist too far down 

the radicalization continuum from where these 

individuals reside; otherwise, the deprogrammers will have no ideological or religious legitimacy in the eyes of their subjects. Second-order 

effects: Implementing this strategy has pitfalls 

related to Islamic cultural sensitivity issues, the 

matter of who would implement the strategy in 

various regions of Syria and Iraq, and different 

interpretations of traditional Sunni behaviors 

and perspectives and their degree of extremism.
66

• Physically Inhibit the Movement of Remaining 

Forces: Islamic State personnel still in the field 

should be isolated and channeled into increasingly smaller geographic areas. The intent is 

to create rings of containment around the 

personnel—initially by means of US and allied 

fires and encircling coalition forces—so they are 

unable to escape the remaining enclaves within 

which they are operating. This strategy also 

serves to fix the personnel in time and space, 

which further allows them to either be targeted 

and killed in place or captured and detained. 

Containment rings established farther outside of 

the enclaves in which the Islamic State members 

are trapped are used as security checkpoints for 

identification purposes so fleeing members can 

be arrested. Technology is quickly advancing 

to the point where automated facial-recognition systems can be loaded with Islamic State 

social media imagery (pictures and videos) to 

create datasets that may allow for Islamic State 

personnel identification at checkpoints. Nevertheless, for the time being, security checkpoints 

should be supported by biometric and facial 

recognition technologies to facilitate the capture of better-known Islamic State members. 

Inhibiting Islamic State financial support and 

moneymaking opportunities would also further 

serve to curtail the migration of extremist fighters. Second-order effects: Few downsides exist to 

following this policy; however, the appropriate 

Islamic State personnel countermove would 

be to fall back, go to ground by breaking into 

smaller and smaller groupings, and merge 

into local refugee flows or find refuge in safe 
67

houses. At this point, the Islamic State fighter 

threat begins to become more of a law enforcement matter.160 Unfortunately, such a physical 

cordon creates black-market opportunities for 

human traffickers. Safe passage into Turkey 

has been quoted as costing $20,000–30,000 for 

senior Islamic State operatives. Also, one trafficker boasted he had smuggled 50 Syrian and 

foreign Islamic State fighters, often dressed like 

women to bypass border patrols, into Turkey.161

• Psychologically Deter Outflow from Syria and 

Iraq: In addition to creating physical impediments to Islamic State personnel movement 

within Syria and Iraq, the psychological component of the extremists seeking to leave the 

territorial ruins of the caliphate—either laterally to another battlefield or to their countries of 

origin—should be targeted. This strategy would 

require psychological operations to create a 

deterrent to travel in the minds of Islamic State 

members by convincing them conditions in 

locations they seek to migrate to are even more 

inhospitable than their present circumstances. 

But, from an implementation perspective, so 

many countries of origin exist that focusing this 

message at specific nationals would be difficult, 

as would getting the message to them in the 

first place. For this reason, the message should 

160. Greg Myre, “Where Did the IS Fighters 

Go?,” NPR, January 1, 2018, https://www.npr.org

/sections/parallels/2018/01/01/574967338/where-did

-the-islamic-state-fighters-go.

161. Eric Schmitt, “Thousands of ISIS Fighters Flee in Syria, 

Many to Fight Another Day,” New York Times, February 4, 2018, 

https://www.nytimes.com/2018/02/04/world/middleeast

/isis-syria-al-qaeda.html.
68

be tailored to nationals whose countries of 

origin are in North America, Europe, and other 

Western regions. Second-order effects: Amateurish attempts at such focused propaganda could 

have the opposite effect, or, if the program is 

successful, could drive more extremists into 

Syrian regions controlled by the Assad regime 

where more Islamic State safe havens exist.

Organization-Focused Response Policies

In addition to the policies discussed above, the 

larger Islamic State organization should be targeted 

with countermigration policies involving direct 

and indirect control functions. (A debate existed at 

one point on the centralized versus decentralized 

organizational components of al-Qaeda, with Bruce 

Hoffman advocating the importance of al-Qaeda 

Central and Marc Sageman advocating a leaderless 

and networked perspective.)162 The countermigration 

policies would focus on the following.

• Disrupting Hierarchical Command and 

Control: The Islamic State command-and-control element is centralized and traditional 

in nature, like a hierarchical, industrial-age 

162. See Elaine Sciolino and Eric Schmitt, “A Not Very 

Private Feud over Terrorism,” New York Times, June 8, 2008, 

https://www.nytimes.com/2008/06/08/weekinreview

/08sciolino.html. Both perspectives are accurate, with one form 

of organizational structure dominating during some time frames 

and in some locales and the other form dominating during and 

in others.
69

organization.163 This structure was particularly 

evident after the caliphate was established in 

mid-2014, with its headquarters in Al-Raqqah, 

Syria. This Islamic State direct-control capability—while a legacy—still functions to 

some extent, even with the death of Abu Bakr 

al-Baghdadi and while other senior leadership 

remain at large. Targeting and disrupting this 

command-and-control capability is required to 

help degrade the organization’s ability to order 

extremist fighter lateral battlefield migration 

from Syria–Iraq to other regions. Second-order 

effects: Further Islamic State devolution into a 

more networked entity is the expected result of 

this policy. Although this policy would not end 

Islamic State terrorist and insurgency threats in 

various regions of the world, it would eliminate 

the group’s capacity to reconstitute a territorial 

caliphate and direct centralized attacks as a projection of power to other regions of the globe, as 

al-Qaeda undertook in the 9/11 attack upon the 

United States via its safe haven in Afghanistan, 

then under Taliban rule.

• Disrupting Network Influence: The other 

component of Islamic State command and control is network-based and indicative of flatter 

twenty-first-century organizations that have 

increased information flows and quicker reaction and decision cycles than traditional entities. 

163. Examples of the centralized organizational plan can 

be seen in the Islamic State primary documents analyzed in 

Christoph Reuter, “Secret Files Reveal the Structure of Islamic 

State,” Spiegel International, April 18, 2015, http://www.spiegel

.de/international/world/islamic-state-files-show-structure-of

-islamist-terror-group-a-1029274.html.
70

Instead of direct-control oversight of the tasking of Islamic State personnel, this component 

is related to influencing network and individual nodal behaviors. Islamic State networks 

reside on numerous social media platforms and 

applications, so achieving influence capability 

is required across numerous cyberspace venues 

to reach extended elements of the Islamic State 

collective.164 Engagement in this domain would 

require a cross-platform and cross-application 

social media counternarrative campaign. This 

campaign—conducted in multiple languages, 

with an emphasis on English, French, and 

German—would be directed at Islamic State 

attempts to influence members of its affinity 

grouping in Syria and Iraq to engage in lateral 

emigration across globally dispersed battlefields or jihad within Western states. Technologies that may be used for such a campaign 

include specialized software offering an “online 

persona management service,” with which one 

US servicemember could control up to 10 online 

social media identities on the Web.165 Secondorder effects: This policy would further serve to 

devolve the Islamic State—specifically its cyber 

caliphate component—into numerous weak 

and fragmented voices, instead of allowing it to 

164. For instance, a network view of the Islamic State 

Facebook collective can be found in Gregory Waters and Robert 

Postings, Spiders of the Caliphate: Mapping the Islamic State’s Global 

Support Network on Facebook (New York: Counter Extremism 

Project, May 2018).

165. See Nick Fielding and Ian Cobain, “Revealed: US Spy 

Operation That Manipulates Social Media,” Guardian, March 

17, 2011, https://www.theguardian.com/technology/2011

/mar/17/us-spy-operation-social-networks.
71

be unified by means of more encompassing narratives. One way to potentially achieve such an 

end state would be to flood the multiple social 

media venues used by the Islamic State network 

with competing and contradictory messages. 

For example, advanced generative bots that can 

write 20,000 lines of online text a second would 

be ideal for such a mission.166

Higher-Level US Foreign Policies toward Syria and Iraq

The proposed countermigration policies directed 

at Islamic State members—fighters, cubs, and wives—

cannot be conducted within a foreign policy void 

vis-à-vis US security interests in Syria and Iraq. The 

policies must be deconflicted with, and would ideally 

complement and support, US policies directed toward 

the present geopolitical realities of those states. The 

proposed foreign policy guidance is as follows.

• Continued Limited Cooperation with 

Authoritarian Regimes: One of the coordination issues related to countermigration policies 

in Syria and Iraq is competing—and even hostile—entities, such as the various foreign state 

and nonstate coalitions, each of which has a 

certain percentage of the extremist fighter and 

familial demographic set residing within its 

operational areas of control. Given that Islamic 

State narratives and actions have elevated the 

group to the unenviable position of being the 

enemy of all—even to its former allies al-Qaeda 

166. See Douglas Haven, “The World’s Most Prolific Writer 

is a Chinese Algorithm,” BBC News, August 29, 2018, http://

www.bbc.com/future/story/20180829-the-worlds-most-prolific

-writer-is-a-chinese-algorithm.
72

and affiliates of al-Qaeda—some form of ongoing deconfliction and limited targeting cooperation with “the enemies of our enemies” to 

further ensure extremist fighters cannot migrate 

out of the region and ultimately can either be 

eliminated or captured in theater should be 

sustained. (The “enemy of all” statement may 

be contested in that Islamic State funding—at 

least in the past—is alleged to have come from 

donors in Saudi Arabia and Qatar, and, in 

many instances, Turkey has engaged in questionable policies toward the Islamic State.)167

The fact that, as these cooperative activities are 

taking place, each individual entity and coalition is jockeying to maximize its own relative 

position against each other should not be forgotten. Also, ethically and legally, the United 

States cannot engage in any form of cooperative efforts, even limited ones, with authoritarian regimes if, by doing so, war crimes or other 

atrocities may result.

• Containment of Iranian and Russian 

Influence in Syria: Such containment would look 

to balance against both Iran and Russia, while 

ensuring the Islamic State threat is still firmly 

addressed. This policy would include “deterring 

Iranian forces and militias from pushing close 

167. See, for instance, Martin Williams, “FactCheck Q&A: Is 

Saudi Arabia Funding ISIS?,” 4 News, June 7, 2017, https://www

.channel4.com/news/factcheck/factcheck-qa-is-saudi-arabia

-funding-isis; “Fighting, While Funding, Extremists,” New York 

Times, June 19, 2017, https://www.nytimes.com/2017/06/19

/opinion/saudi-arabia-qatar-isis-terrorism.html; and Ahmet S.

Yayla and Colin P. Clarke, “Response: Turkey’s Double ISIS 

Standard,” Foreign Policy, April 12, 2018, https://foreignpolicy

.com/2018/04/12/turkeys-double-isis-standard/.
73

to the Israeli border, disrupting Iranian lines of 

communication through Syria, preventing substantial military escalation between Israel and 

Iran, and weakening Shia proxy forces,” as well 

as “deterring further Russian expansion in the 

Middle East from Syrian territory and raising 

the costs—including political costs—of Russian 

operations in Syria.”168 At the same time, this 

approach recognizes the requirement to prevent a resurgence of the Islamic State or the rise 

of another jihadist group such as al-Qaeda or 

its affiliate, the Al-Nusrah Front.169 The current 

perception is the Syrian civil war has de facto 

been won by the Assad regime because it has 

not been defeated. The regime is now in the process of regaining many of its former territories 

following the resumption of its despotic, dynastic rule, which is grudgingly preferred—by the 

United States and its coalition—to Islamic State 

suzerainty. Although liberal-democratic control 

of all Syrian territories is ideal, this end state is 

not presently achievable with Russian forces on 

the ground protecting their client state.

• Mitigation of the Effects of Iraqi 

Fragmentation: The state of Iraq is increasingly devolving into three sectarian zones, with 

the Shia population clustered from the center 

toward the east, the Sunni population clustered 

from the center toward the west, and the Kurds 

concentrated within the northwestern region. 

This devolution has been exacerbated by Shia 

domination of the political process for the 

168. Seth G. Jones, Developing a Containment Strategy in Syria

(Washington, DC: CSIS, May 2018).

169. Jones, Developing a Containment Strategy.
74

branch’s own self-interests, Kurdish empowerment due to increasing autonomy related to 

the group’s militarization and territorial gains, 

and Sunni population linkages to the Islamic 

State—especially via former personnel of the 

Assad regime. State fragmentation in Iraq 

would create new institutional voids in the state 

within which the Islamic State could begin to 

reconstitute itself. Although the United States 

should attempt to shape the Iraqi political landscape, it only has a limited capacity and will 

to do so. Prudence suggests the United States 

should continue to back the Kurds via the presently existing patron–client relationship while 

attempting to interface with and cultivate the 

support of the nonradicalized Sunni populations. Attempting to influence the Shia populations has been and will continue to be difficult, 

even more so now that Iranian influence is 

extremely well entrenched. Whether pressing the Iraqi Shia leadership to offer concrete 

political and economic goods to address Sunni 

concerns and feelings of governmental alienation can at this point be realistically achieved 

is unknown. If the fragmentation of Iraq should 

someday come to pass, the Islamic State should 

not be allowed to fill the security voids in the 

geographic seams between the three competing 

sectarian elements of that nation.

Counter-Foreign Terrorist Fighter Programs

The UN counter-FTF programs seek to stop 

the flow of FTFs into states—typically at states’ 

borders (though also via international aviation 
75

security-screening standards). The US Army War 

College KSIL tasking focuses primarily on stopping the 

outflow of Islamic State extremist fighters (and their 

cubs and wives) from Syria and Iraq.170 The counterFTF programs and the KSIL tasking can and should be 

thought of as front- and back-end policy approaches 

to an important international security concern. 

Extremist countermigration policy coordination and 

deconfliction issues related to the FTF programs are 

as follows.

• Countermigration Policy Interfaces and 

Overlaps: Policy and implementation seams 

and overlaps will exist between the proposed 

front-end policies and the preexisting back-end 

programs that are geographic in nature (those 

taking place in Syria and Iraq vis-à-vis a multitude of internally focused initiatives) and that 

differ in terms of the national authorities and 

regional coalitions participating in them. The 

front-end policies are military-focused ones set 

in foreign operational environments. The backend programs are security services and law 

enforcement ones set in domestic environments. 

Liaison will thus be required between United 

States Central Command and the appropriate 

UN bodies—composed of various directorates, 

working groups, and teams in coordination with 

the Counter-Terrorism Implementation Task 

Force, which is composed of 38 international 

170. The 2014 counter-FTF implementation plan includes 

FTFs from the Islamic State, the Al-Nusrah Front, and other 

al-Qaeda-affiliated groups. Given the far larger numbers of 

Islamic State FTFs (and their familial dependents), the KSIL 

tasking has an increased focus on the members of this terrorist 

organization, though the tasking could also be applicable to the 

Al-Nusrah Front and other al-Qaeda affiliates.
76

entities—to ensure these efforts work in concert 

with one another.171 Specific functional areas of 

countermigration policy related to coordination 

and deconfliction include deradicalizing, physically inhibiting travel, targeting Islamic State 

financial support and moneymaking opportunities, psychologically deterring migration, 

reintegrating into society captured personnel 

who have been released or who have served 

their prison sentences (especially if they are 

stateless), and disrupting direct (hierarchical) 

and indirect (network) organizational control.172

Joint Force Recommendations

The US Joint Force has four specific 

recommendations related to extremist fighter 

migration and the inherent threat potential that 

results from such migration. These recommendations 

are based on both higher-level, strategic, and 

complementary considerations. The recommendations 

are as follows.

• Review and Validate Datasets and Estimates: 

The discrepancies, gaps, and inconsistencies 

171. See “The Counter-Terrorism Implementation Task 

Force (CTITF),” UN Victims of Terrorism Support Portal, https://

www.un.org/victimsofterrorism/en/about/ctitf.

172. For thoughts on Islamic State financial trajectories, 

see Patrick B. Johnston and Colin P. Clarke, “Can the Islamic 

State Survive Financially?,” Lawfare, May 14, 2017, https://

www.lawfareblog.com/can-islamic-state-survive-financially. 

One component of Islamic State financial targeting is now being 

coordinated by means of the Terrorist Financing Targeting Center. 

See US Department of the Treasury, “US and Saudi Arabia to 

Co-Chair New Terrorist Financing Targeting Center,” May 21, 2017, 

https://www.treasury.gov/press-center/press-releases/Pages

/sm0092.aspx.
77

encountered when researching the Islamic 

State and foreign extremist fighters are causing 

immense levels of confusion. Individual datasets and estimate information appear valid; 

however, when they are cross-checked, the 

integrity of the numbers quickly becomes dubious because of contradictions and discrepancies 

between them. Information voids exist with no 

reliable numbers or estimates available related 

to Islamic State fighters recruited in Syria and 

Iraq or lateral battlefield migration out of the 

former lands of the caliphate. A comprehensive 

review of the datasets and estimates related 

to Islamic State foreign and extremist fighters 

is recommended—as well as the filling in of 

information voids—so baseline numbers can 

be generated and validated in support of Joint 

Force activities to avoid wasting resources in 

unproductive areas.

• Islamic State Expansion into New Provinces: 

The demise of the territorial caliphate has 

resulted in multiple strategic options—or countermoves—being available to the Islamic State. 

The group foresaw the need for such strategic 

countermoves once it entered the caliphate’s 

decline-and-fall era by August 2016, if not prior. 

The new dominant strategy the group is following is that of microcaliphate creation as a component of a greater global insurgency. Islamic 

State COAs related to the development and 

expansion of the new provinces—representative 

of these microcaliphates—should be analyzed 

by the Joint Force. Such analysis would include 

future lateral battlefield migration options once 

the new provinces and the most likely COAs 
78

had been established. These activities should be 

studied in depth by means of gaming, simulation, and strategic red teaming efforts.

• The Demise of the Territorial Caliphate: 

Al-Qaeda, just like the Islamic State, is being 

subjected to the second- and third-order effects 

resulting from the demise of the territorial 

caliphate. New pressures on al-Qaeda will 

present themselves, as will new opportunities 

for the group. One line of thought is al-Qaeda 

and its affiliates have greatly benefited from 

the military attention of the United States and 

its allies on the Islamic State. As an outcome, 

al-Qaeda has replenished its ranks, with some 

32,200 to 44,200 extremist fighters now globally 

deployed—a larger estimated force than that 

presently possessed by the Islamic State. Indeed, 

according to Bruce Hoffman, “ISIS can no longer 

compete with al-Qaeda in terms of influence, 

reach, manpower, or cohesion.”173 On the other 

hand, the Islamic State has now become a direct 

global-insurgency competitor to al-Qaeda in 

its new strategic manifestation. These circumstances beg the questions: Over time, will the 

Islamic State take over more and more of the 

radical Islamist (Sunni) global insurgent market 

from al-Qaeda? Will al-Qaeda be able to dominate this niche area successfully? Or will some 

sort of equilibrium be reached, with a dual organizational insurgency ensuing? The Joint Force 

should also engage in al-Qaeda postcaliphate 

COA analysis by means of gaming, simulation, 

and strategic red teaming efforts.

173. Bruce Hoffman, “Al-Qaeda’s Resurrection,” March 6, 

2018, https://www.cfr.org/expert-brief/al-qaedas-resurrection.
79

• Update the Unified Command Plan (UCP): 

The UCP is “a classified executive branch 

document prepared by the Chairman of the 

Joint Chiefs of Staff (CJCS) and reviewed and 

updated every two years that assigns missions; 

planning, training, and operational responsibilities; and geographic areas of responsibilities 

to [combatant commands].”174 The components of the UCP that strategically coordinate

counter-Islamic State and counter-al-Qaeda 

efforts across the geographic and functional combatant commands should be updated now that 

a postterritorial caliphate exists.175 The update 

would benefit from the three Joint Force recommendations previously discussed. Further, 

all-of-government counterterrorism considerations must be better aligned with the UCP, the 

2017 National Security Strategy of the United 

States, and the subordinate National Strategy for Counterterrorism released in October 

2018.176 Of concern is the radical Islamist threat 

has morphed over the course of roughly two 

decades from a singular al-Qaeda global 

174. Andrew Feickert, The Unified Command Plan and 

Combatant Commands: Background and Issues for Congress, R 42077 

(Washington, DC: Congressional Research Service, July 17, 2012). 

See also “Unified Commands, CENTCOM & Components,” 

United States Central Command, http://www.centcom.mil

/ABOUT-US/COMPONENT-COMMANDS/.

175. Feickert, Unified Command Plan; and “Unified 

Commands, CENTCOM & Components.”

176. See Donald J. Trump, A New National Security Strategy 

for a New Era (Washington, DC: The White House, December 

2017); and Donald J. Trump, National Strategy for Counterterrorism 

of the United States of America (Washington, DC: The White House, 

October 2018).
80

organizational threat into a contemporary, 

dual, al-Qaeda and Islamic State global organizational threat. Although describing this situation as “one Hydra head getting hacked off and 

two growing in its place” may be premature, 

victory over the radical Islamist threat remains 

virtually elusive. This problem should at least 

cause some strategic reflection—and, possibly, 

reevaluation—on the part of the United States, 

given that it, now 19 years beyond 9/11, is $2.8 

trillion deeper in national debt as a result of its 

response to the attacks.177

177. Aaron Mehta, “Here’s How Much the US Has Spent 

Fighting Terrorism Since 9/11,” Defense News, May 16, 2018, 

https://www.defensenews.com/pentagon/2018/05/16

/heres-how-much-the-us-has-spent-fighting-terrorismsince-911/.
A POLICY RESPONSE TO ISLAMIC STATE 

EXTREMIST FIGHTER BATTLEFIELD 

MIGRATION

ABOUT THE AUTHORS

ROBERT J. BUNKER was formerly an adjunct research 

professor in the Strategic Studies Institute at the US 

Army War College and is currently an instructor 

at the Safe Communities Institute, University of 

Southern California. Past associations include futurist 

in residence at the FBI Academy and distinguished 

visiting professor and Minerva Chair at the Strategic 

Studies Institute. Dr. Bunker holds university degrees 

in many subjects and has undertaken hundreds 

of hours of counterterrorism and counternarcotics 

training. He has authored hundreds of publications.

ALMA KESHAVARZ is an international security 

analyst. She is a postdoctoral fellow at Carnegie 

Mellon University and an associate with Small 

Wars Journal–El Centro. She previously served 

on the policy planning staff at the Department of 

State and was a nonresident fellow in terrorism and 

security studies for TRENDS Research and Advisory. 

Dr. Keshavarz holds a PhD, a master of applied 

politics degree in political science, a master of public 

policy degree, and a bachelor of arts degree in English.
US ARMY WAR COLLEGE

Major General Stephen J. Maranian

Commandant

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Dr. Carol V. Evans

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Colonel George Shatzer

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US ARMY WAR COLLEGE PRESS

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Mr. Richard K. Leach

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Ms. Lori K. Janning

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Mrs. Jennifer E. Nevil