Saudi-Iran Crisis: Why It Matters in the Fight Against ISIS

— -- 2016 is off to a bad start in the Middle East.

Divisions between Sunni and Shia factions flared up violently after the Saudi government executed a top Shia cleric, Sheik Nimr al-Nimr, as part of a mass execution of 47 people on Jan. 2. The Saudi government claimed the executed individuals were terrorists. Protests began almost immediately in Iran and the Saudi Embassy in Tehran was set on fire. Embassy staff managed to escape unharmed.

The Saudi government responded by severing diplomatic relations with Iran and gave its diplomats 48 hours to leave the country. Foreign Minister Adel al-Jubier said the Iranians have an “aggressive policy in the region, which aims to destabilize security and stability, and to provoke conflict and wars.” The Saudis recently banned all flights from Iran. Bahrain and Sudan have also severed diplomatic ties with Iran. The United Arab Emirates downgraded its diplomatic ties with Iran.

"We believe that diplomatic engagement and direct conversations remain essential in working through differences and we will continue to urge leaders across the region to take affirmative steps to calm tensions," State Department spokesman John Kirby said in a statement Monday.

Iran and Saudi Arabia have been fighting proxy wars in Yemen and Syria, but these new tensions could have serious implications for the West. At the end of 2015 both nations participated in American-led talks in New York aimed at seeking a political solution. But the severing of diplomatic ties between the two threatens the future of those negotiations, and therefore threatens the American strategy for resolving that devastating conflict and eventually defeating ISIS.

The second and more immediate alarm for Americans is the potential rise in oil prices. The Wall Street Journal reports Monday that oil prices rose over concerns about Middle East tensions and weak economic data out of China. Investors worry that tensions between Saudi Arabia and Iran could disrupt the flow the oil. Recent data shows that the two countries combined produce about 13 million barrels of crude oil a day.

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