Iranians gather during a demonstration against the execution of prominent Shiite Muslim cleric Nimr al-Nimr by Saudi authorities, at Imam Hossein Square in the capital Tehran on January 4, 2016. Tensions between Iran and its Sunni Arab neighbours reached new heights as Saudi Arabia and Gulf allies cut or downgraded diplomatic ties with Tehran in a row over the execution of a Shiite cleric. AFP PHOTO / ATTA KENARE / AFP / ATTA KENARE        (Photo credit should read ATTA KENARE/AFP/Getty Images)
Why can't Iran and Saudi Arabia get along?
02:07 - Source: CNN

Editor’s Note: Aaron David Miller is a vice president and distinguished scholar at the Woodrow Wilson International Center for Scholars and author of “The End of Greatness: Why America Can’t Have (and Doesn’t Want) Another Great President.” Miller was a Middle East negotiator in Democratic and Republican administrations. Follow him on Twitter @aarondmiller2. The opinions expressed in this commentary are his.

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Aaron Miller: Confused about the sharp escalation of tensions between Iran and Saudi Arabia?

Here are six key takeaways to get you started.

CNN  — 

Confused about the sharp escalation of tensions between Iran and Saudi Arabia? Want to try to get your arms around the complexities of a crisis that is likely to be with us for some time to come?

Here are six key takeaways to get you started:

Aaron David Miller

1. This crisis reflects the deep and longstanding sectarian divide between Sunnis (roughly 85% of Muslims) and Shia (15%) throughout the region.

And at the same time, it’s about a power struggle for control and influence between Saudi Arabia – one of the Arab world’s most important Sunni states – and Shia Iran. This phase of the crisis may eventually abate; but that power struggle will remain one of the defining features of the Middle East for years to come.

2. Saudi Arabia genuinely fears a rising Iran. Iran’s support for a local insurgency in Yemen, in Saudi Arabia’s backyard, and for Bashar al-Assad’s regime in Syria are cause for concern. So is the Iranian nuclear agreement, which has given Iran access to billions of dollars that had been blocked by sanctions and left it still with a large nuclear infrastructure.

But the Saudi decision to execute 47 individuals, including a prominent Saudi Shia cleric, was also designed to send signals to Shia and Sunni opposition elements at home that, as ever, a price will be paid by those who challenge the monarchy in word or deed.

The Saudis are playing the sectarian card to rally Sunnis and to distract attention from rising budget deficits and cutbacks in government benefits that are virtually forced on the regime by the collapse in oil prices.

3. The Iranian-Saudi crisis will almost certainly distract attention from the war against the Islamic State, boost the fortunes of the Assad regime and make any solution to the Syrian crisis that much more difficult.

Even if a way can be found to lower the temperature between Riyadh and Teheran and get them talking again, the odds against functional and effective cooperation to end Syria’s civil war are slim to none. If anything, Saudi-Iranian tensions will up the ante and turn Syria into a more intensified proxy war between the two states.

Iran will intensify support for the Alawite-Shia Assad regime and the Saudis for ISIS’s Sunni opponents. And those sectarian tensions will play out in Iraq, too, as Iran consolidates its influence over the Baghdad-based Shia government and expands its reach through pro-Iranian Iraqi Shia militias.

4. Right now, Iran appears to be the big loser in the current round of tensions, but it shouldn’t be counted out. The UAE, one of its largest trading partners, has downgraded relations as have Sudan, Bahrain and Kuwait.

Iran’s willingness to allow, or at least to fail to prevent, the sacking of the Saudi Embassy in Teheran has left it more isolated at a time when the implementation of the nuclear agreement should have bucked up its status.

The U.N. Security Council condemned the attacks on Saudi diplomatic facilities in Iran without mentioning the Saudi executions. And Iranian hardliners will use the Shia-Sunni escalation with the Saudis to gain ground at the expense of Iranian President Hassan Rouhani in the parliamentary elections set for next month.

5. For now, the Saudis appear to be the only winner in the current crisis. Determined to ensure their internal security and worried that the United States hasn’t been tough enough with Iran, the Saudis asserted themselves and are reaping at least temporary gains. Iran’s image has been tarnished, and the Saudis have assembled a Sunni coalition to isolate Iran diplomatically.

Still, Riyadh is riding a sectarian tiger. Iran may well try to capitalize on the outrage among Shia that the beheading of the popular Shia sheikh has evoked and try to stir up trouble among Shia in Bahrain and in Saudi Arabia, where they represent 15% of the Saudi population, and increase their support for the Houthis in Yemen.

6. The Iranian-Saudi crisis leaves the United States with enormous headaches and challenges as it attempts to straddle a fence with insufficient credibility and influence with both sides. Even though Saudi Arabia is a U.S. ally of sorts, recent strains have undermined Washington’s influence with Riyadh and created a situation where it has little leverage to resolve the current crisis.

At the same time, the United States needs the Saudis in its war against the Islamic State. As for Iran, given the fact that one of President Barack Obama’s key foreign policy legacies lies partly in Iran’s hands – the nuclear deal – Washington can’t be too critical of the Iranian role either without risking the deal’s collapse.

Even if U.S. diplomacy manages to tamp down this round of escalation, the Saudi-Iranian cold war represents just the kind of crisis that’s likely to remain unresolved and not amenable to U.S. political persuasions.

Last week was Iran week – from the tensions over the detention of 10 U.S. sailors, to the prisoner/hostage swap to the implementation of the nuclear agreement.

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