Over the last decade, sectarianism has increased in the Middle East and influenced regional politics. The debate over a potential rift between Sunni and Shia Muslims began with the victory of the Islamic Revolution in Iran in 1979. Iran’s proclaimed intention of exporting this revolution to neighboring countries alarmed the latter’s political regimes, particularly in the Gulf States in immediate proximity to Iran, where the state systems are monarchies, and the majority of the people are Sunni. The reality of sectarian strife has become clear since the United States-led invasion of Iraq in 2003, which was followed by Iran’s increasing influence in the country and the Iraqi Shia parties’ control of the government. The strife erupted into a sectarian civil war during 2006-2008, when some armed Sunni groups intensified their attacks in response to the U.S.-led coalition and the government’s policies, while the Salafi-Jihadists escalated the conflict. With the outbreak of the Arab Spring in 2011, some of its revolutions such as in Bahrain, Syria and Yemen have evolved into sectarian and geopolitical confrontations among regional states, particularly Gulf States and Iran. Operation “Decisive Storm” in Yemen, in effect since 2015, clearly exemplifies this geo-sectarian struggle. Finally, the execution of Saudi Shia dissident cleric Nimr Baqir al-Nimr in January 2016 led to an open confrontation between Saudi Arabia and Iran after Shia angry demonstrators set fire to the Saudi embassy in Tehran. Saudi Arabia responded by cutting off its diplomatic relations with Iran.