OUR JIHAD:

Internally, Sistani's words directly addressed the fractured Iraqi political class. They are helping reunite Iraq's dithering Shi'a factions under the strategic priority of fighting terrorism, and boosting moderate Sunnis.

Ayatollah Sayid Ali Al-Sistani is the leading Islamic Shi'a scholar, playing a preeminent role similar to the Pope amongst Catholics. Housed in modest dwellings in the holy city of Najaf, he has been the mainstay of calm and moderation in Iraq. His fatwas throughout the last decade urging Shi'a-Sunni unity have been credited for holding back Iraq from all-out civilian strife at the height of sectarian tensions in 2006-8. So when Sistani issues a call to arms, our world stands up and takes notice. [...]

Externally, Sistani's words have sent tremors into the corridors of power in the Arab and broader Muslim world. Sistani's words were understood as a call for jihad: a holy war against the terrorists. It represents by far the strongest statement Sistani has ever issued since assuming leadership of the Shi'a Muslim world.

The political message to the Gulf and Ankara is clear: if they continue to fund and sponsor extremist Sunni militant groups, the leadership of the Shi'a Muslim world will no longer stand idly by. If a fight is inevitable, they are ready. 

The enormity and seriousness of the ISIS threat on Iraq brings the United States and Iran onto the same strategic side. Shared interests in the stability of Iraq and the need to eradicate terrorists create a significant opening for cooperation between the two countries. The last time the sides came together was in the aftermath of 9/11, when Iran offered support for the US war on the Taleban. Iran's President Hassan Rouhani has seized on this opportunity, calling today on "all to practically and verbally confront terrorist groups," indicating Iranian willingness to cooperate with the US in the shared goal of fighting terrorism. If this cooperation takes place, prospects for increased trust in the western-Iranian nuclear negotiations may follow.

Pessimists see the ISIS attack as resulting in Iraq's breakup and the boosting of terrorism in the region. Optimists see a great opportunity for Shi'a-Sunni unity against extremists, and the moves toward an American-Iranian rapprochement that can be transformative for peace and security prospects in the Middle East.

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