Small Wars Journal

ISIS Resurgence and the Sunni-Shi’a Schism

Thu, 12/04/2014 - 6:30pm

ISIS Resurgence and the Sunni-Shi’a Schism

Kyler Ong


This article argues that the recent resurgence of the Islamic State of Iraq and al-Sham (ISIS), otherwise known as the Islamic State, gained momentum during the Syrian civil war in 2011. Coinciding with the final withdrawal of the United States and coalition troops in Iraq, ISIS has surfaced as one of the most prominent radical insurgent groups in Iraq – after al-Qaeda – that threatens the social and security fabric struggling to unite the sectarian-divided country. However, there exists a gap in literature failing to examine whether the Sunni-Shi’a schism is the main force multiplier of the status quo conflict and insurgency. This paper investigates the ancient sectarian rivalry in Iraq that dates all the way back to the period of Prophet Muhammad, the composition of ISIS and its motivation, the timely concurrence of the Syrian civil war and U.S. troop withdrawal, and finally recommends courses of action for the government of the United States and Iraq. Through all this, this paper tries to piece together the impetus that has driven the resurgence of ISIS. The picture that emerges is a group that is largely an indirect offspring of the Syrian civil war that benefited from the final withdrawal of the U.S. and international troops as well as the political instability and sectarianism that continue to plague Iraq.

They have closed ranks and pledged bay’ah to Baghdadi, for our emir in our Iraq and ash-Sham.

-The ISIS nasheed


On 29 June 2014, a goal to establish a Sunni-majority Islamic caliphate in the Islamic world under the leadership of Abu Bakr al-Baghdadi was announced in the midst of internal chaos and political uncertainty in Iraq following American withdrawal three years earlier. Yet, the terror group who had made such a bold declaration is not, strictly speaking, a brand new phenomenon. The roots of the Islamic State of Iraq and the Levant, now known as the “Islamic State” (ISIS), dates all the way back to the world’s most widely-known terrorist group, al-Qaeda. Following several amalgamations of the parent group, ISIS came under the leadership of Abu Bakr al-Baghdadi, who of Iraqi origin, rebranded the group under the banner of ISIS in April 2013.  The recent resurgence of ISIS under the leadership of Abu Bakr al-Baghdadi gained momentum during the period of the American troops withdrawal in Iraq and the Syrian uprising in 2012.  However, its brutality and notorious intractability has been denounced by other terror group, including al-Qaeda, and has propelled intra-fighting between ISIS and other terror groups, such as Syrian rebel group Jabhat al-Nusra (JN). Yet, ISIS has been largely successful in controlling swaths of land (in Iraq, at least) despite the internal conflict with other likeminded Islamic jihadist groups in the region.

Suffice to say, ISIS has been so effective at terrorizing people through the exploitation of media outlets and ethnic cleansing of non-Sunnis that it has significantly empowered itself through terror in order to gain control of land. Furthermore, the political instability inside Iraq ever since the departure of American and coalition troops in the country and the marginalization of Sunnis in Iraq since post-U.S. withdrawal phase after 2011 has instigated the growing Shi’a-Sunni rivalry instigated by Nouri al-Maliki’s favoritism over the country’s Shi’a majority (Gulmohamad 2014, 4-5). It appears that while other Islamic terror groups, such as al-Qaeda or Jemaah Islamiyah in Southeast Asia, has sought to make advances in their respective operation theater, ISIS’s support base is unprecedented, with an estimate of 20,000 to 31,500 active fighters ventured by the Central Intelligence Agency (Sciutto, Crawford and Carter 2014, n.p.). In light of that, the question remains as to how paramount the Sunni-Shi’a schism is in Iraq in empowering the recent resurgence of ISIS in the country. It appears that while the sectarian divide plays a role in encourage ISIS to metastasize in Iraq, it was the Syrian civil war in 2011 that provided an impetus and empowerment for ISIS to enter Iraq and consolidate its power in such a short period of time.

Literature Review

While open source literature has ventured to examine the ISIS phenomenon by addressing its origin and the political puzzle of ISIS in the region, there exists a gap in literature pertaining to the main force multiplier that has enabled ISIS to garner such a huge support base and successfully conquer vast swaths of Iraqi lands in the span of a few months since June this year. Moreover, a lack of sources attributing the current crisis in Iraq to the Sunni-Shi’a schism as a main driver for ISIS to exploit also calls for further re-examination into the root of the issue.

A survey of the literature on ISIS has underscored the role of local tribal groups in collaborating with ISIS. ISIS has exploited the disillusionment prevailing in Sunni-dominant areas, especially in Anbar and Mosul, to intensify anti-Maliki sentiments after the failure of the Iraqi government to ensure a smooth transition for the former Sons of Iraq (coalition of Sunni tribal groups who worked with U.S. coalition forces and the Iraqi army to defeat al-Qaeda) to be integrated into the Iraqi army and police has left them feeling marginalized once again (Dermer 2014, n.p.). Nonetheless, Zana Gulmohamad proposes that while tribal sentiment in Iraq is generally anti-Maliki due to the government’s discriminatory policies against the Sunnis, many tribal leaders have actually denounced ISIS and pledged their support for the central government in their confrontation against the terror organization (Gulmohamad 2014, 4). In fact, it has been well-documented that the ISIS’s draconian and brutal style of governance and modus operandi have angered many Sunnis and a majority of the former Sons of Iraq have steered clear of the ISIS uprising in 2014 (Gulmohamad 2014; Stratfor 2014; Katzman 2014, 10).

Another school of thought that has been put forth by experts on the resurgence of ISIS is the role of the Assad’s regime as a patron sponsoring ISIS and furthering their interests in Iraq. Despite being anti-establishment – viz., anti-Assad, – some has posited that ISIS is collaborating with al-Assad in secret oil deals; there is a general consensus in this camp involving the Arab Gulf States and the Syrian National Council that the Syrian regime is facilitating ISIS activities because of their control over oil fields and their discernible importance in impeding moderate rebel movements in Syria (Gulmohamad 2014, 7).

Furthermore, the U.S. withdrawal from Iraq in 2011 and the Syrian Civil War also gave ISIS the momentum to launch its offensive in both countries by giving it safe havens and the ambition to train and recruit jihadists in the region by taking advantage of the political vacuum and chaos provided by these two concurrent events; these two events have been postulated by some as the reasons for the rise of ISIS to power (Warrick 2014, n.p.). In addition, many have also consented to use of brutality by ISIS as a method of consolidating power amidst the turmoil without any Western interferences; as Jessica Lewis of the Institute for the Stud of War offers, “intimidating the local security forces through bombs and their homes by targeting key leaders for assassination, making them a softer target for the assault…” was the reason why ISIS was able to make gains in Mosul, a city of almost two million people (Warrick 2014, n.p.). Their extent of their cruel modus operandi is reinforced by the public executions of civil activists and Western journalists that have surfaced in the media in recent months.

Research Design and Methodology

The research method of this paper will be qualitative and deductive in nature. For the reason that statistics would probably not be the answer to understanding beliefs and ideologies, qualitative data would better serve the purpose of this paper. Due to the constraint in undergraduate research, methods used would have to be restricted to open source literature. The information will be largely dependent on an examination of scholarly sources that have provided analysis on political situation in Iraq that had led to the rapid rise of ISIS. Furthermore, it will assess the composition of the ISIS members and foreign fighters and attempt to identify their motive for joining the extremist group in the bid to reveal any sectarian rationale that would prove or disprove the hypothesis. While literature has demonstrated that the withdrawal of American forces and other instabilities (i.e., the Syrian Civil War) have played a major role in ISIS gaining momentum in Iraq, this paper will focus on examining the Sunni-Shi’a schism in Iraq and how it has contributed to the rise of ISIS. Finally, the paper will also provide policy recommendations for the U.S. and Iraqi government in their fight against ISIS.

The hypothesis will be tested through strenuous analysis of the extent of the Sunni-Schism as a fundamental cause for ISIS’s resurgence. The paper will be both explanatory and predictive because it seeks to establish not only a casual link for the rise, but also demonstrate possible policy approaches that could be used to advance the central government’s interest in the war against ISIS. The independent variable is this study will be the Sunni-Shi’a sectarian divide and the dependent variable will be rise of ISIS. There is one foreseen limitation in this paper and that is the literature gap in examining the impact of the ancient animosity between the Sunni and Shi’a on empowering ISIS in Iraq. This paper will thence attempt to examine the issue through deductive analysis with the limited literature available in open sources.

Hypothesis: The Sunni-Shi’a Schism in Iraq Propelled the Resurgence of ISIS in Iraq.


A quick examination of the ancient schism must be looked into in order to fully comprehend the current crisis with ISIS. Sunni-Shi’a schism began after the death of Prophet Muhammad in 632 AD which prompted a divide between Sunni Muslims and Shi’a Muslims; the former believed that the successor of Muhammad had to be deemed by the community’s elites and thus favored Abu Bakr, the first caliph and father-in-law of Muhammad, while the latter believed that the successor had to come from Muhammad’s family, and thus supported Ali ibn Abu Talib, the son-in-law and cousin of Muhammad (ProCon 2009, n.p.). Ultimately, the Sunnis prevailed as the successor and began a campaign in Arabia against the Byzantine Empire, establishing Arabic influence throughout the Middle East, including Iraq, and undermined Shi’a Islam in the region.

From 1509 onwards, however, the Ottoman Turks launched a region-wide offensive in Arabia, driving the rift between Sunni and Shi’a even further as its conflict with the Safavids in Iran over the control of Iraq (which had Shi’a holy places in An Najaf and Karbala) led to a series of protracted battles; Iraqi Sunnis also suffered during the Safavid’s reign (1623-1638). During the Heshemite reign, while it seemed as if the main issue of that time was nationalism, the religious conflict continued to rear its ugly heard. Even after the appointment of Faysal as king, during the period between 1921 and 1936, Sunni Muslims dominated the political elite. Tensions with Shi’a Iran continued as each tried vying for regional supremacy and border disputes remained the source of contention (Abdullah 2011, 131-232). In addition, the Sunni elites and the British sought to ensure that the Shi’a remained under-represented (134). When Saddam Hussein came into power, as a Sunni Muslim, he faced oppositions from Shi’a Muslim opposition groups, such as the Ad Dawah, which was supported by the Shi’a -dominated Iran; this, and border skirmishes eventually cumulated in the 1980 Iran-Iraq War (ProCon 2003, n.p). Today, the Sunni-Shi’a divide continues to be an influential factor in modern-day politics between Iraq and Iran, as well as a source of internal chaos in Iraq.

Modern Variation of Schism

The composition of ISIS members and fighters helps to shed some light on an ancient rivalry in Iraq. In particular, the question remains as to whether Iraq’s ancient religious divide has recently fueled a resurgence of conflicts between its Sunni minority and Shi’a majority. It is evident that ISIS is dominated by Sunni Muslims and that the waves of foreign fighters coming from all across the world are from the Sunni sect (Zelin 2014, n.p.). Nonetheless, how much do these figures represent an indiscernible rivalry other than a mere coincidence that Sunni population constitutes about 87-90% of the total Islamic population (Pew Research Center 2009, n.p.)? It appears that ISIS has been recruiting followers in the West through social media platform to join “a Sunni-led religious state spanning from the Mediterranean to the Persian Gulf” (Abi-Habib 2014, n.p.) Taking into account the history of marginalization that Iraqi Sunni have suffered, it is not a surprise that U.S. withdrawal in 2011 and the social chaos created at the start of the Syrian civil war were precipitated by the escalation of violence demonstrated by opportunistic Sunni militants (who were the persecuted sect in both countries) against these weak central governments. In Iraq, especially, the persecution of the al-Maliki government against the country’s Sunni population after U.S. withdrawal also stoked tensions between the country’s two main sects. How ISIS gained momentum to become such a threat to Iraq’s national security and stability lies in the exploitation of the struggle between the two sectarian groups.

Yet, does it suffice to say that ISIS was able to resurrect itself primarily because of the Sunni-Shi’a schism? While it appears that the schism played a huge role in ISIS’s recruitment strategy, ISIS really experienced a surge during the Syrian civil war. As General David Petraeus underlines,

That element [ISIS] really built itself in the Syrian war, where over time it was able to take control of certain of the oil production facilities and started generating revenue. It could capture weaponry…ISIS really grew out of the growing flame of the Syrian civil war, and as its got bigger, more powerful it started to push back into Iraq. (Public Broadcasting Services 2014, n.p.)

The U.S. withdrawal in 2011 merely coincided with the onset of the Syrian civil war, which accorded ISIS an enormous opportunity to manipulate and exploit the political and social chaos to gain territories and oil fields. This empowerment spilled across the border to Iraq, which was at that time experiencing not only a weakened central government with dwindling American presence, but also a protraction of Sunni disillusionment from being disenfranchised; Iraqi Sunni Arabs, especially those who joined the Sons of Iraq, the tribal coalition that fought alongside U.S. and Iraqi security forces and was promised incorporation into the Iraqi government upon defeat of al-Qaeda, no longer saw an incentive for them to support the Iraq under the Shi’a dominated Maliki regime after the Awakening. However, to claim that ISIS gained momentum for resurgence because of the Sunni-Shi’a schism is half of a lie; after all, the schism dates 1382 years back and has not revived only recently. The Syrian civil war was the one that provided the impetus, weapons, territorial gains and confidence for ISIS to cross over to Iraq and conquer swaths of land.

Policy Recommendation

In certain areas of Iraq, the Sunni population, which has become so disenfranchised once again by the government’s failure to deliver, celebrated and welcomed ISIS forces. In light of that, this paper will recommend several strategic steps that could possibly turn the tide and regain the trust of the minority population in the bid to defeat ISIS.

Despite being an outshoot of al-Qaeda, ISIS’s rift with al-Qaeda is discernible from its nasheed as well as its ideological differences. ISIS adopts a very fundamentalist and extremist interpretation of Islam whose goal and perspectives do not parallel that of al-Qaeda; for instance, the former deems itself the “victorious sect” and targets Shi’a Arabs, whom it regards as deviants and apostates, rather than the West. Growing tensions between ISIS, al-Qaeda and the Syrian Jabhat al-Nursa could be exploited by inciting further weakening through intra-fighting, and where the dynamics of the battlefield could be changed to the point where the respective key parties are willing to negotiate some kind of settlements – since ISIS is a multifaceted issue and threat, it must involve the Syrians. The respective central governments and the Arab Nations must lead the negotiation and serve as a reliable conduit point for the negotiations.

It is also recommended that the Iraqi central government try to gain the trust and secure the lives of the Sunni majority. Firstly, the central government must heed the advice of Grand Ayatollah Sistani, who has prescribed a “rapid formation of a government, an inclusive government” that constitutes the three main elements – Shi’a, Sunni Arabs and Kurds. It is imperative to bring the fabric of the society back together and band the Kurds, Sunni and Shi’a in this fight. The Iraqi government must forge a path to reconciliation with its disenfranchised population and convince them that it will deliver its promise of addressing past wrongs.

Secondly, in the bid to regain trust and distant Sunni Arabs from ISIS, it must tarnish the reputation of ISIS. After all, the draconic rule of al-Qaeda was what spawned the Sunni Awakening beginning late 2006 to 2007, whereby Sunni tribesmen who were former allies with al-Qaeda turned against their terrorist organization after growing disillusionment with al-Qaeda’s modus operandi propelled tribal leaders to reconcile with the central government and U.S. security forces. In order to achieve that, long-term incentives must first be given and guaranteed; a United Nations or Arab League intervention is encouraged to ensure that they serve as witnesses to any agreements made by passing a resolution.


The Sunni-Shi’s schism plays an important role in exacerbating the ISIS threat as well as allowing ISIS to gain a foothold in Iraq in a span of a few months. However, the resurgence of the militant group originates from the Syrian civil war, while coincided with the vacuum left by the withdrawal of U.S. troops from Iraq. This facilitated the rapid metastasis of ISIS in Iraq, not to mention that the increasing use of social media by jihadi terrorists which attracted a cadre of Sunni foreign fighters to Syria and Iraq. This disproves the original hypothesis and deems it null.

The purpose of this paper is to examine the role of Sunni-Shi’a schism in Iraq in the recent conflict with ISIS in the country. While open source literature has analyzed the group’s modus operandi, recruitment strategies, and emphasized on its ability to attract foreign fighters from all across the world, none has sought to provide a thorough examination on the role of the divide in attracting an unprecedented (viz., in numbers and origin) support base. Only by delving into the historical conflict between Sunnis and Shi’a can it then reveal the underlying root for ISIS success. The paper thence adopts a quantitative and deductive research approach which cumulates in the use of open source literature including media and scholarly sources. The findings in this paper have contributed an understanding of the primary factor for ISIS’s resurgence. Future research could focus on the examination of ISIS’s foreign fighters and the external and personal reasons for joining ISIS and not al-Qaeda. This could hopefully help shed some light on the intra-differences between the jihadi terrorist organizations.


Abdullah, Thabit. 2011. A Short History of Iraq. New Jersey: Pearson Education Limited.

Abi-Habib, Maria. “Jihadists Step Up Recruitment Drive.” The Wall Street Journal, June 25, 2014. Accessed October 22, 2014.

Alvi, Hayat. “The Diffusion of Intra-Islamic Violence and Terrorism: The Impact of the Proliferation of Salafi/Wahhabi Ideologies.” MERIA Journal 18, no. 2 (2014): 38-50. Accessed September 13, 2014. EBSCOhost, APUS Library.

Dermer, Philip. “The ‘Sons of Iraq’, Abandoned by Their American Allies.” The Wall Street Journal, July 1, 2014. Accessed October 16, 2014.

Gulmohamad, Zana Khasra. “The Rise and Fall of the Islamic State of Iraq and al-Sham  (Levant) ISIS.” Global Security Studies 5, no. 2 (2014): 1-11. Accessed September 13, 2014. EBSCOhost, APUS Library.

Katzman, Kenneth. “Grievances Unresolved as U.S. Withdraw.” Congressional Research Service, 2014. Accessed October 17, 2014. EBSCO Host, APUS Library.

Petraeus, David. Interview by Public Broadcasting Service, July 29, 2014. Accessed October 22, 2014.

Pew Research Center. “Mapping the Global Muslim Population.” Religion and Public Life Project, 2009. Accessed October 22, 2014.

ProCon. “Timeline, Pre-History – 1989.” Last updated on April 13, 2009. Accessed October 18, 2014,

Sciutto, Jim, Jamie Crawford, and Chelsea Carter. 2014. “ISIS Can ‘Muster’ Between 20,000 and 31,500 Fighters, CIA Says.” CNN, September 12. Accessed September 13, 2014.

Stratfor. “Iraq: Islamic State Makes Gains Despite Opposition.” Stratfor Analysis, August 1, 2014. Accessed October 17, 2014, EBSCO Host, APUS Library.

Terrorism Research and Analysis Consortium (TRAC). “ISIS: Rifts between ISIS and Other Terror and Rebel Groups.” Accessed October 16, 2014.

Warrick, Joby. Interview by Brian Todd. CNN, June 18, 2015. Accessed October 17, 2014,

Zelin, Aaron. “The Return of Sunni Foreign Fighters in Iraq.” Washington Institute for Near East Policy, 2014. Accessed October 22, 2014. ESBCO Host, APUS Library.

About the Author(s)

Kyler Ong is a student at the School of Security and Global Studies, American Military University.


Bill C.

Wed, 12/10/2014 - 11:57am

In reply to by Outlaw 09

Given, as you point out, the civil war nature of this conflict between Sunni and Shia,

But with specific consideration to our national interests -- as I have described them above,

Then which group (Sunni or Shia) should we be leaning toward to help?

And which group should we be leaning toward to defeat?

(Herein, no longer "oil" -- but rather "favorable transformation" -- now being the matter that determines who we are most likely to get in bed with?)

Outlaw 09

Wed, 12/10/2014 - 11:34am

In reply to by Bill C.

Taken from Russian Interfax today:

15:20 IS has up to 70,000 militants of various nationalities in Syria, Iraq - Russian general

This has gone far pass the previous Sunni Shia divide debate---this has taken on a civil war aspect now between Sunni and Shia across Syria and Iraq and with the oil price war that the KSA is driving --which is focusing on Iran and Russia and both of their relationships with Assad it now has an international aspect.

And by the way IS has declared war as well on Russia--with Chechnya as the starting point and it is simmering as well in the Crimea.

And still no national level strategy to be seen anywhere.

Bill C.

Wed, 12/10/2014 - 11:31am

A question for the more-knowledgeable and more-informed:

Is there a group -- Shia or Sunni -- that is more-progressively inclined, to wit: a group that is more likely to embrace greater transformation along modern western political, economic and social lines. And, thus, a group (Shia or Sunni) that is more likely to become our "natural ally" via its embrace of such western-like reforms?

Likewise, is there a group (Shia or Sunni) that is more likely to dig in its heals, resist such "modernizing/modernization" and, instead, seek alternative ways of life and alternative ways of governance?

The U.S./the West, re: its national interests, to best be served by (1) identifying and allying itself somewhat with the more-progressively-inclined group (Shia or Sunni); this, so as to work more effectively against the less-progressively-inclined group (Shia or Sunni)?

Outlaw 09

Sat, 12/06/2014 - 5:07am

One main fallacy of this article and it is a major misstep--while interesting it did not go into the ongoing regional hegemon dispute between Iran as the "supreme" defender of the global Shia community and that of the KSA which views itself the "defender" of global the Sunni community.

Yes it is historical in nature and yes it is often stated it goes back to the question following the death of Mohammed BUT the Supreme Religious Leader Khomeini in 1979 started stating many times after he became the Supreme Ruler that Iran was going to create and defend the "Green Crescent" which if one looks at the maps is the "old Silk Road route" linking all Shia from India over AFG via Iraq, Syria and ending in Lebanon.

What is also missing is an analysis of the "revolutionary nature of Shiaism" that Khomeini injected into current day Iran and is bitterly defended by the IRGs.

Which if one checks the current locations of Shia dominance you will notice they have to a degree succeeded.

The KSA on the other hand has been busy building a Sunni wall around Iranian efforts and has also to a degree been successful.

If you then look at the role the Sunni insurgent groups played in Iraq from 2003 to 2010 you can see the KSA efforts in supporting them.

After 2010 look at the KSA and other Sunni rulers support for and towards the IS and you will see a not so subtle approach to using IS to balance against the Shia/Iranian actions especially Hezbollah and Assad--especially against Assad as he attempted to destroy the majority Sunni population.

Also not mentioned is the interaction between Iran and the then AQI and now IS and the IS and Assad relationship as the IS balanced themselves against other Islamist groups and also what they have declared to be their bitter enemy--"the Shia".

Then couple that with the inherent KSA dislike of Russian support for Iran and Assad and one wonders just where the falling oil price strategy came from?

That needed to be included in this article but was not---again we far to often look at the symptoms not the reasons that drive populations to support one side or the other in this region of the world.

What was also missed and is critical in just how the IS formally the QJBR and then AQI interacted and now is supported by the other major Iraqi Sunni insurgent groups, Ansar al Sunnah, 1920 Brigades, Islamic Army in Iraq and al Duri's Baathist/Islamist group --that is a major failure in this article.

Regardless of just how bad IS has behaved---they are still supporting IS--and the core question should have been WHY which was barely if at all touched.

I am not so sure that the US civilian leadership even understands all of the above and yet they are rushing to formulate a policy as they attempt to deploy back into an area they claimed we were pulled out of as the "mission" was completed in 2010 and Iraq was ready to support itself.