Men holding a picture of Bahraini Shiite cleric Sheik Isa Qassim, right, and a caricature of the Saudi king, participate in an anti-Saudi demonstration in Tehran on Sept. 9. (AFP via Getty Images)

In what's becoming almost a recurring theme, Iran's Foreign Minister Mohammad Javad Zarif wrote an op-ed in the New York Times attacking Saudi Arabia, a long-standing geopolitical foe of the Islamic Republic.

The opinion piece, titled "Let Us Rid the World of Wahhabism" — a reference to the puritanical strain of Islam incubated in the kingdom — pinned the blame for Islamist terrorism largely on the legacy of Saudi support for extremist groups, as well as the country's financing of orthodox mosques around the world.

"Over the past three decades, Riyadh has spent tens of billions of dollars exporting Wahhabism through thousands of mosques and madrasas across the world," Zarif wrote in the New York Times. "From Asia to Africa, from Europe to the Americas, this theological perversion has wrought havoc."

Its influence, Zarif insists, is toxic: "Though it has attracted only a minute proportion of Muslims, Wahhabism has been devastating in its impact. Virtually every terrorist group abusing the name of Islam — from Al Qaeda and its offshoots in Syria to Boko Haram in Nigeria — has been inspired by this death cult."

The enmity and rivalry between Iran and Saudi Arabia — which see themselves at the vanguard of Shiite and Sunni Islam, respectively — is well-documented. Last week, as WorldViews noted, senior officials in both countries traded barbs as the annual hajj pilgrimage to Mecca got underway. This year, tens of thousands of Iranians have been barred from joining the pilgrimage after talks over security and logistics collapsed in the wake of a deadly stampede in 2015 that may have claimed thousands of lives, including hundreds of Iranian pilgrims.

Iran's supreme leader posted an angry statement last week, accusing the Saudis of being shoddy custodians of Islam's holy sites. Saudi Arabia's top cleric responded, linking Iranian antipathy to the pre-Islamic faith of Persia, now modern Iran — the sort of rhetoric that, in another context, violent militants would perhaps invoke to justify sectarian slaughter of apostates.

This plays into the hands of Iranian officials who are forever keen to point out the connection between Saudi Arabia and Sunni fundamentalist outfits such as al-Qaeda and the Islamic State.

"It is not the supposed ancient sectarian conflict between Sunnis and Shiites but the contest between Wahhabism and mainstream Islam that will have the most profound consequences for the region and beyond," Zarif wrote.

Iran, of course, is hardly a good guy here.

Zarif's op-ed avoids any mention of his own regime's role in fomenting religious violence across the region, including its direct support to a string of proxy militias in Lebanon, Syria and Iraq. Representatives of its two regional foes — Saudi Arabia and Israel — both clamor loudly in Washington about Iranian perfidy in the Middle East, a concern which animates a considerable segment of the American foreign policy establishment.

After a recent trip to Saudi Arabia, former U.S. diplomat Zalmay Khalilzad argued in Politico that the kingdom could play a real role "in balancing Iran and perhaps negotiating about ending the civil wars in the region." Yet, in a piece that's intended to be flattering to the Saudis and their current efforts toward political and economic reform, Khalilzad also introduces a curious admission.

As part of "an unprecedented policy of honesty," Saudi officials opened up to him about the dangerous game they played in backing religious insurgencies of the past. "We misled you," one official told Khalilzad, when asked about earlier denials over support for Islamist extremism. The Saudis say their actions were motivated by the imperatives of the Cold War and competition with Iran. Khalilzad goes on:

But over time, the Saudis say, their support for extremism turned on them, metastasizing into a serious threat to the Kingdom and to the West. They had created a monster that had begun to devour them. “We did not own up to it after 9/11 because we feared you would abandon or treat us as the enemy,” the Saudi senior official conceded. “And we were in denial.”

This doesn't exactly aid Zarif's thesis about the Saudis' bad behavior. But it doesn't quite hurt it either.

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