The Shia-Sunni Split and Its Impact on U.S. National Security
This paper examines the historical and theological origins of the Shia-Sunni divide within Islam, tracing the split from the death of the Prophet Muhammad in 632 CE through the Battle of Karbala and into the modern era. It describes the geographic distribution of each denomination, outlines core doctrinal differences, and analyzes how centuries of sectarian tension escalated into geopolitical conflict across the Middle East. The paper then focuses on how this ongoing divide — through events such as the Iranian Revolution, the Iran-Iraq War, the Gulf War, the U.S. invasions of Afghanistan and Iraq, and the rise of ISIS — has directly shaped U.S. foreign policy decisions and posed persistent challenges to American national security.
- Introduction: Islam's Two Primary Denominations: Demographics and doctrinal overview of Sunni and Shia Islam
- The Historic Denominational Split: Origins of the split after Muhammad's death in 632
- Sectarian Violence and Geopolitical Power Struggles: Definition and roots of Sunni-Shia sectarian conflict
- The Iranian Revolution and Its Aftermath: Shiite quietism, Pahlavi's coup, and Khomeini's rise
- U.S. Military Involvement and Escalating Sectarian Conflict: Gulf War, 9/11, Iraq invasion, and insurgency
- The Syrian Civil War and ISIS: ISIS advance, Sunni displacement, and Shiite militia retaliation
- Conclusion: Ongoing Implications for U.S. National Security: Persistent sectarian tensions and dilemmas for U.S. strategy
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What makes this paper effective
- Provides solid historical grounding before moving to contemporary geopolitical analysis, giving readers the context needed to understand modern conflicts.
- Draws a clear causal thread from the 7th-century theological split to 21st-century U.S. military decisions, making abstract religious history tangible and relevant.
- Uses specific named events, dates, and actors (Battle of Karbala, Ayatollah Khomeini, Saddam Hussein, ISIS) to anchor general claims in concrete historical fact.
Key academic technique demonstrated
The paper demonstrates effective chronological scaffolding — it builds an argument across time by sequencing causes and effects, showing how each political and military development emerged from prior sectarian tensions. This technique helps readers track the compounding nature of the conflict rather than treating individual events in isolation.
Structure breakdown
The paper opens with a demographic and doctrinal overview of Sunni and Shia Islam, then reconstructs the 7th-century origins of the split. A long central section traces political and military escalation from World War I through the post-2003 Iraqi insurgency. The final sections examine the Syrian Civil War, ISIS, and the dilemma facing U.S. and Iraqi forces trying to stabilize a region where Sunni communities fear both ISIS and Shiite militias. The conclusion implicitly frames the sectarian divide as an ongoing U.S. national security concern.
Introduction: Islam's Two Primary Denominations
Many religions have different denominations, and Islam is no exception. The two primary denominations of Islam are Sunni Islam and Shia Islam. The majority of Muslims across the globe are Sunni, estimated at roughly 85% to 90% of the global Muslim population. The remaining smaller share — approximately 15% — are Shia. Further distinctions indicate that most Shias belong to the tradition known as Twelver, with the rest of the Shia identifying with other traditions.
"Twelver" refers to the number of descendants of Muhammad that this sect of the Shia recognize as legitimate successors. Another group is referred to as the Seveners, since they recognize only seven descendants who were official caliphs of Islam. This is further complicated by the concept of Occultation, which refers to a messianic figure — the Mahdi — who is born but goes into hiding in order to remain safe. Critics have described the concept of Occultation as a pious fraud that promotes the idea of waiting faithfully for a messiah who will renovate the world by eradicating evil and restoring justice. Moreover, a period of Occultation permits an elaborate system of communication between believers and agents of the Mahdi, as only certain privileged individuals are believed to be capable of conducting the sacred duty of contacting the hidden Mahdi on behalf of the faithful. In this scenario, the Mahdi is said to be physically present but in hiding. In other scenarios, no one presides over the Shia faithful, who all await the Mahdi's return. An objective scholar can readily see the possibilities for controlling communities of believers without authentic authority to do so.
In any given Muslim community, Sunnis tend to be in the majority. This is true for Muslim communities across most of the Arab world and in Africa, China, South Asia, and Southeast Asia. Globally, the largest number of practicing adherents of the Sunni tradition reside in Indonesia. The Shia, on the other hand, constitute the majority of Muslim populations in Azerbaijan, Bahrain, Lebanon, Iran, and Iraq. The largest population of Shia Muslims is found in Iran. Pakistan occupies a unique position as the country with both the second-largest Sunni population and the second-largest Shia Muslim population in the world.
References
Caliphate. (2015). In Encyclopaedia Britannica. Retrieved from http://www.britannica.com/EBchecked/topic/89739/Caliphate
Hendawi, H., Abdul-Zahra, Q., and Yacoub, S.N. (2015, January 6). In Iraq's war against extremists, a quiet sectarian purge. AP. Retrieved from
Hazleton, L. (2010). After the prophet: The epic story of the Shia-Sunni split in Islam. Aylett, VA: Anchor.
Pollack, K.M. (2015, February 4). ISIS is losing in Iraq. But what happens next? The New York Times, p. A25.
Shuster, M. (2007, February 12). Chronology: A history of the Shiite-Sunni split. National Public Radio (NPR). Retrieved from http://www.npr.org/2007/02/12/7280905/chronology-a-history-of-the-shia-sunni-split
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