Sectarianism is gradually turning into a horrifying non-fictional monster that has opened its jaws wide as it prepares to devour entire regions in the Middle East and some parts of North Africa.

A wave of unprecedented division and intolerance has submerged the two main branches of Islam, Sunni and Shia, jeopardizing centuries of coexistence, peace and political unity. The sectarian conflicts tearing apart entire countries like Iraq, Syria and Yemen, and turning them into bloody battlefields heralds disaster for the peoples of the region. Given the scope of the conflicts, serious attention should be given to the motives and the basic arguments underlying this great schism in the Muslim world.

The Sunni-Shia schism is not new, but what can explain the recent clashes between the two parties? Religiously speaking, it is safe to say that both agree on the principle teachings and rituals of the Quran and the hadith, or the collected stories of the Prophet Muhammad, which constitute a major moral guide in Islam. Even 1,400-year-old debate over the Prophet’s legitimate successor cannot singlehandedly explain the recent sectarian turmoil since it has no practical significance today. Instead, the answer lies in the modern history of the conflict, which gained significant momentum following Khomeini’s 1979 revolution in Iran.

To understand Iran’s role in the Sunni-Shiite tensions, the question of religion’s role in the political life of Muslim countries is instructive. Though many Arab and Muslim societies have changed considerably due to urbanization and modernization, traditional structures continue to exist side by side with modern forms. Within these structures, religion plays a significant role in shaping and determining public life and political systems. Religion also becomes a decisive instrument with which to justify a political side over the other and to legitimize despotism. Authoritative regimes rely heavily on religious discourse to defend their interests and consolidate power. Rather than strengthening a tendency toward democratic power, the Arab Spring actually gave rise to Islamist parties that oppose the notion of a secular state. It is this significant presence of religion that has contributed to the dissimulation of social and political disputes beneath the trappings of religion.

The ongoing Sunni-Shiite conflicts also serve as an outlet for some regimes to export their domestic crises and seek internal support by drawing public attention towards the “common enemy.” Saudi Arabia, for example, uses Iran as a lightning rod for delaying political reforms and as a pretext for cracking down on Shiite protests in the kingdom. Its theocratic counterpart, Iran, uses a similar pretext for the very same purpose.

There are, however, two other major factors influencing both regional and global rivalry over the Middle East, which is, after all, one of the most geopolitically strategic parts of the globe: Khomeini’s revolution and the Shiite state he helped establish broke with West, thus complicating the scramble for regional dominance on the part of the western superpowers.

Since Khomeini’s revolution and the toppling of Shah in 1979, Iran has undergone a long period of estrangement with western superpowers, mainly the U.S., as well as their allies from the Sunni bloc represented by the Gulf countries, within which Saudi Arabia plays a role of leadership. Khomeini’s ambitions were to expand Iranian influence across the region and to export the Shiite revolution by investing in Shiite minorities in predominantly Sunni Muslim countries. Iran plays on sectarian tensions as a safety valve to alleviate pressure or possible military intervention of the West against it. Pro-Iran Shiite political groups have enabled Khomeini’s men to negotiate their role in the turmoil of the Middle East, thus making them indispensable. Those groups guarantee political presence of a Shiite state in Lebanon, Iraq, Yemen and Bahrain, in addition to their strong ally, Syria.

Given the geopolitically strategic position of the Middle East, the western superpowers have historically involved themselves in the affairs of the MENA region. In fact, western involvement in the region began  during the colonial era, continued throughout the Cold War and is still happening today, largely through the ongoing rivalry between the U.S. and Russia. The U.S. and the rest of the West have often sided with Sunni regimes (with some exceptions, such as Saddam’s regime following Iran-Iraq war or the Shiite government in Iraq).

The Saudi-Emirati bloc has maintained comfortable relations with the U.S. despite the fundamentalism of the Saudi government. The bloc has received political, military and diplomatic support from both Democrat and Republican presidents; the case of the Saudi-led coalition in Yemen is self-evident. Russia, on the other hand, seems to spare no means to back up the Shiite bloc, prolonging the life of Bashar al-Assad’s regime in Syria and embracing Iran. Russia, as a result, has resorted to military intervention in Syria, alongside Iran and Hezbollah, in hopes of saving Assad.

This political polarization triggers Shiite-Sunni tensions and further provokes religious fervor at a time when every party blames past disputes for the legitimacy of its position today. What was long seen as an insignificant difference in Islam has now become, at least for many Muslims, a determining element for religious identity and belonging, on the one hand, and a question of political loyalty on the other.