Sunni-Shia Tensions in the Iran-Iraq War

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The Iran- Iraq war was one of the longest and bloodiest conflicts of the 20th century. Costing billions of dollars and millions of lives, the significance of the decision by the respective actors to proceed with a war that was proving to be so domestically detrimental cannot be overstated, and the result, whilst seemingly somewhat of a stalemate, would be a major factor in the shaping of the future of the Middle East. Sunni- Shi’ite tensions, whilst entrenched for centuries, certainly came to a head following the pro- Shi’ite revolution in Iran that sought to spread its message across the Arab world, threatening the domestic security of the Sunni Baath party. However, to suggest that it was the sole factor would be to neglect the short term contributory catalysts that can be considered the true causes of the decision to undertake all out warfare. By first assessing the level and significance of Sunni-Shiite tensions, this essay will provide a platform to then cross analyse the significance of these tensions with other contributory, arguably more major, factors; the geopolitical climate that dictated the region, the role of Arab nationalism, and a traditionally realist perspective on the pursuit of regional superpower status. This essay will, due to word limitations, focus explicitly on the domestic and regional factors.

One of the areas of cross cultural significance in which the animosity between Sunni’s and Shiites became apparent, and manifested itself in an excuse for hostility, can be found in a series of purges in Southern Iraq by Hussein. The Baath party rounded up Shiites in the area, and those of Iranian nationality, and those who could not legally prove their Iraqi citizenship, were bussed into Iran. This sectarian step not only antagonised relations between the nations, but served to evolve Khomeini’s embryonic grip on power (Wright, 1985). In the fall out of the revolution, it was far from definitive that Khomeini’s power would be absolute, however Saddam’s actions allowed him to unite the warring clerical factions behind the a common enemy, cementing his position and establishing him as the indisputable head of Iran. The security of Shiite support allowed the Ayatollah to engage in a war under the masquerade of religious virtue, however, as will be discussed, the realist goals of self aggrandisement, security, and establishment as head of the balance of power, were the propellers beneath the Iranian war machine. As Wright notes, ‘religion and religious sectarianism were not important in Iraq [or Iran’s] decision to go to war- they have only become important after the fact’ (1985, pg. 840).

Another manifestation of Shi’ite-Sunni animosity can be found in Iraqi paranoia over the possibility of a Shi’ite revolution. The demographic compilation of Iraq lent itself to the possibility of popular revolt, and the ruling Baath party was constantly on edge over how best to suppress this threat without being so antagonistic as to incite an all out civil war. The revolution in Iran threatened these balance, as it provided the suppressed population of Iraq with a bordering brethren whom had unity with their cause. Shi’ite Muslims in Iraq regarded Khomeini as their natural religious leader, who in turn used this eminence to advocate the overthrow of Hussein and begin the Islamification of secular Iraq. Indeed, a brief glance at Iraqi history lends validitiy to Hussein’s paranoia. Wright (1985, pg.  840) notes how during the Iraq war on the Kurds, Iran provided weapons and sanctuary to the oppressed Kurds, and on three separate occasions in 1974, ’77,and ’79, Iran secretly supported Shiite anti- Baath organisations. After the revolution, Khomeini’s government continued to attempt to foment revolution in neighbouring Arab states (Azhary, 1984, pg.4). Clawson and Rubin (2005)  note the support Tehran provided for Shi’ite terrorism attempts, believed to be responsible for the 20 deaths of Iraqi government officials in 1980 alone. Whilst Iraq had retaliated by supporting a coup to install Bakhtiar, the Shah’s last Prime Minister, it failed, and war was considered to be a natural extension of the attempt to displace the Shiite supporting Iran leadership. The goal of the attack then, as well as the removal of Ayatollah Khomeini, was to send a signal of discredit to those who supported Khomeinis revolution, and provide an ominous example to domestic factions considering the possibility of emulating Khomeini’s Islamic coup (Swearingen, 1988, pg. 411).

Having discussed the significance, of lack thereof, of religious alignment and cross-cultural antagonisms in catalysing the war, it is significant to assess the other contributory factors to determine the major cause that triggered the hostilities.

Swearingen argues that, whilst Sunni/Shi’ite tensions played a role, they are ‘most convincingly interpreted as a struggle for status as the region’s most dominant power’ (1988, pg. 411). Prior to the Iranian revolution, Iran was the dominant military power in the gulf region. It enjoyed US support, and as Milton- Edwards notes, it had become ‘identified with the West’ (2011, pg. 127). However, following its revolution and establishment of a government dictated by a commitment to Islamic fundamentalism, with designs on propagating it’s revolution across the Middle East, the power balance, in the eyes of the West, had to be redressed, and thus support was lended to Hussein’s Baath party. Iraq saw the crippling effect the revolution had had on Iran’s military and economy, and thus attacked. The seizure of Western Khuzistan, to be further discussed later, was heralded, and a key withdrawal insistence was the return of three Arab islands occupied by the Shah’s navy since 1971. Swearingen insists that this insistence, this accumulation of land and heady demand was evidence of Iraqi posturing as the regional superpower. Indeed, he notes how the Deputy Prime Minister of Iraq said it was the stated objective or Iraq to ‘prove in battle that it is stronger than Iran and fully capable of defeating it’. This offensive realist interpretation of the causes of the war carries significant credence, as whilst Sunni-Shi’ite tensions had been in place for centuries, it was only once the eternally powerful, and perceived regional superpower, was showing weakness that Iraq struck in pursuit of self aggrandisement and tilting the balance of power in its favour.

Swearingen further notes the ideological clash as a possible contributing factor. Iraq was ruled as a secular state, predicated on the ideals of Arab Nationalism. Due to the stark gap between the compilation of the ruling classes, and the cultural reality of the politically disenfranchised public, with a 20% Sunni minority ruling a nation comprised of 60% Shi’ite and 20% Kurds, both groups who had faced significant repression, it was impossible for Hussein’s rule to place any kind of emphasis or significance on religion. Instead, Hussein propagated a policy that stressed Arab unity, seeking coalescence with his Arab neighbours, and espoused a socialist doctrine that would provide a masquerade for his authoritarian ruling. Conversely, as Grigoriadis and Ansari (2008, pg. 329) note, Khomeini sought to synthesis religion with nationalism. The revolution, they further claim, resulted in a displacement of nationalist ideology, and instead he disseminated a pan- Islamic worldview, seeking to spread the revolution beyond the confines of national borders.

Halliday asserts that it was a conflict over two political systems: the radical republicanism of Baghdad and the monarchical conservatism of Tehran (2005, p. 179). Niblock builds upon this claim, stating that the war was an inevitable regional response to the shift in civil society that followed the Iranian revolution (2008, pg. 495).  Halliday proceeds to introduce the explanatory power of Atavistic determinism to explain the contributory significance of the differing ideologies of the nations. The conflict, whilst having roots in 7th and 8th century Sunni and Shi’ite splits, was far more engineered by the series of layers superimposed by subsequent ruling authorities who have propagated a rivalry by promoting their own interests and differing ideological stances. Indeed, the Iraqi regime encouraged the use of explicit histories local to civilians, utilising the geographical landscape to highlight the differences with its neighbours (Owen, 2004, pg. 64).

A further significant contributing factor to assess is the Geopolitical climate surrounding the incremental increase in hostilities. Swearingen (1988) specifically notes the storied disagreement over the Shatt al- Arab waterway, half of which had been claimed by Iran following the 1975 Algiers accord. The accord, perceived by many as a humiliation to Iraq after it was forced to accede to Iranian demands due to the possibility of Iranian support for a resumption of the Kurdish revolution; Iraq felt it either had to lose a significant portion of the waterway, or face the possibility of losing one of it’s most oil rich regions to Iranian aided Kurds. A key tenet of Hussein’s presidential popularity was his promise to redress the humiliating treaty as he stated “Shatt shall again be, as it has been throughout history, Iraqi and Arab in name and reality” (quoted, ibid.).

Further evidencing the significance of Shatt al-Arab to the escalation of hostilities can be found in the fall out of the Iraqi seizure of the Iranian territory of Khuzistan, a region rich in oil. After Iraq seized the West of Khuzistan, the negotiation for its return centred on Iraqi desire to renegotiate the territorial tenets of the Algiers accord, and Iran was thus compelled to recognise Iraq’s territorial rights to the region (Swearingen, 1988, pg. 408). Wright considers, then, that the war can be considered to be an ‘extension of the politics of border negotiations by means of a military siege’ (1980, pg. 287), a point emphasised by Swearingen who conclusively states that the above provides compelling evidence that ‘the Shatt al- Arab boundary issue was the cause of the conflict” (1988, pg. 408). It can thus be argued that to a large extent, the border and territorial issues between Iraq and Iran can be considered more of a major contributing factor to the war, as it was over these areas that the core disputes were led, and indeed the battles over their capture and defence were the most fierce and focussed.

To conclude, as Milton- Edwards and Hinchcliffe note, ‘it is tempting to portray the Iraq-Iran conflict predominantly in terms of… a religious and political struggle between Sunni and Shi’ite. But both descriptions are misleading and incomplete’ (2008, pg. 87). The predominant causes of the war can be found in a realist interpretation; pursuit of self aggrandisement, and attempts to assert their power in a power vacuum to tilt the balance power in their respective favour. Iraq saw that Iran was crippled by its revolution, a revolution they were diametrically opposed to anyway. Wright (1985, pg. 839) surmises that religion was used by the leaders as a means to foment support; a cause around which to rally, as identified through Khomeini’s utilisation of Shi’ite oppression. Therefore, it can be concluded that  Sunni- Shia tensions cannot extensively explain the Iran- Iraq war. Rather, it can be considered a factor, however more predominantly more one emphasised by the leaders of the warring nations in order to arouse the interest and support of their followers.



  • Azhary, M. (1984) The Iran- Iraq War Croom Helm: Kent
  • Clawson, P. and Rubin, M. (2005) Eternal Iran  Palgrave Macmillan: New Yowk
  • Grigoriadis, I. and Ansari, A. (2008) ‘Turkish and Iranian Nationalisms’  in Choueiri, Y. ed.  A Companion to the History of the Middle East  pp.313- 334 Blackwell: Sussex
  • Halliday, F. (2005) The Middle East in International Relations Power, Politics and Ideology Cambridge: Cambridge University Press.
  • Milton- Edwards, B. (2011) Contemporary Politics in the Middle East Polity Press: Cambridge
  • Milton- Edwards, B. and Hinchcliffe, P. (2008) Conflicts in the Middle East since 1945 Routledge: Oxon
  • Niblock, T. (2008) ‘Civil Society in the Middle East’ in Choueiri, Y. ed.  A Companion to the History of the Middle East  pp. 486- 504, Blackwell: Sussex
  • Owen, R. (2004). State, Power and Politics in the Making of the Modern Middle East  New York: Routledge.
  • Swearingen, W. (1988) ‘Geopolitical Origins of the Iran- Iraq War’ in Geographical Review Vol. 78, No. 4, pp. 405- 416  [Available online] at   Accessed 03/03/2012
  • Wright, C. (1980) ‘Implications of the Iran- Iraq war’ in Foreign Affairs Vol. 59, No. 2, pp. 275- 303 [Available online] at  Accessed 04/03/2012
  • Wright, C. (1980) ‘Religion and Strategy in the Iran- Iraq war’ in Third World Quarterly Vol. 7, No. 4, pp. 839- 852 [Available online] at  Accessed 28/02/2012

Written by: Sam Langtree
Written at: University of Surrey
Written for: Luca Mavelli
Date written: 12/03/2012

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