This Opinion first appeared in Foreign Policy's "Middle East Channel" on July 17, 2012

Sheikh Ahmad al-Assir, a self-proclaimed religious authority with a bushy long beard, is no stranger on the Lebanese scene. His latest incarnation, from his mosque in the coastal town of Sidon, is as a firebrand political Salafist whose objectives transcend the confines of Lebanon.

He is part of a growing movement in Lebanon and other Arab countries in which the Salafists -- acting as guardians for Sunni interests -- are using the civil war in Syria to gain political power and revive the sectarian conflict with their historical foes, the Shiites. In Lebanon, sectarianism has been a primary feature of the country's politics for decades.

"For years, the Shias have been controlling and insulting us (the Sunnis)," Assir told me when I visited him at the Bilal bin Rabah Mosque in Sidon. "They control the security, the government, and politics. They pay Sunnis to back them to try to create fragmentation among us and they threaten us with a sectarian war ... We support the Syrian rebels. Here in the Sidon mosque, we raise money for those who come to pray for the Syrian rebels."

Assir's candor about his hostility toward Shiites is jarring, but reflects the same kind of sectarian strife I heard during a recent trip to Bahrain and the broader Persian Gulf. Some Lebanese remarked that Assir's confrontational rhetoric is new even for Lebanon, where, after decades of conflict among the country's multiple sects, the Lebanese settled on speaking delicately in euphemisms, calling their sectarian feeling "fitna," the word in Arabic for social disorder.

But no longer. Lebanon was never going to escape the fallout of Bashar al-Assad's civil war. It was always a matter of when and how. As the Syrian civil war rages across the Lebanese border, the public debate is raw, and Shiites and Sunnis speak openly about their mistrust for one another. The growing anti-Western, anti-Hezbollah, anti-Iran Salafist movement is flourishing in some mosques and in towns, particularly in northern Lebanon. Hezbollah, the party that has dominated the Lebanese government over the last year, is a particular target for its continuing support of Assad, as he orders the massacres of thousands of civilians.

"One of the features of the Arab spring was Sunni (power) and some Islamist forces feel that they don't have to deal with Iran and Hezbollah on an indirect level any longer. They can face them directly," Ali Amir, a reporter at Al Balad newspaper in Beirut, told me. Amir specializes in Sunni-Shiite relations.

In the Lebanese city of Tripoli, now home to thousands of Syrian refugees who have fled the fighting, another Salafist imam, Selim al Rafei, is a rising power, who many say is more influential than Assir. On a recent Friday, in the background of posters congratulating the newly elected Egyptian President Mohamed Morsi, a leader in the Muslim Brotherhood, Rafei entered the all-male mosque (women are not allowed) to begin his inspirational Friday sermon.

"The Syrian army is killing the people and is supported by Iran, China, and Russia and the U.S. did not interfere to help the Syrian people," Rafei told the worshipers. "Why are they not supporting the Syrians? Because they are Muslims. The West and America are liars. Their lies are exposed and it is a lesson to our people. The only thing that is helpful for Islam is jihad. Jihad will give us back our dignity."

At the end of his sermon, Rafei congratulated President Morsi and said he "will spread Islam in Egypt and throughout the Arab world." Although there was no direct reference to Shiites, it was clear that Rafei's Islam is that of Sunni Muslims.

The connection between Assir and Rafei, if any, is not apparent. And it is difficult to assess the size of their following and that of other Salafist imams.

Assir recently has been in the media spotlight appearing on national television, denouncing Shiites and calling on Hezbollah to give up their weapons. He also leads protests in Beirut against Assad. During my stay in Lebanon, after his appearances on Al Jadeed (New) television, Assir's opponents attacked the television building, located a short distance from my hotel, and set tires on fire in protest. Assir has been making the case in the media that the Shiites across the region are trying to avenge the Sunni rise to power in countries such as Egypt, where the Muslim Brotherhood now holds the presidency.

The symbol of his grievances is a toy rifle, which he says a Shiite Iraqi businessman has mass produced in China and then distributed in Iraq, Jordan, and Lebanon. There is an audio tape inside the toy rifle: after the sounds of rounds of gunfire -- "rat-a-tat-tat" -- a voice could be interpreted as saying, "Kill Saida Aisha." Aisha was one of the wives of the Prophet Muhammad and is considered sacred by Sunni Muslims. According to Sunnis,  Aisha had an important role in early Islamic history, both during Muhammad's life and after his death. Regarded by many as his favorite wife, she was an active figure who was involved in continuing his message.

When I visited Assir, he appeared calm, gentle, and composed. He told an assistant to fetch the toy rifle. Then he played the tape inside, which was difficult to make out, but the name Aisha was audible. "The Iranian project started all of this," he explained. "Iran's project is to establish the vilayet e-faqih (supreme clerical rule) in the region. I was with the resistance (the term he uses for Hezbollah), but now I am politically their enemy."

It would be easy to dismiss Assir and other Salafist imams, and in fact, some Lebanese intellectuals I met reduced their antics to a temporary phenomenon that will soon lose its luster.

That may well be true, but the Salafist opposition in Lebanon, which is aimed directly against the Iran-Hezbollah-Assad axis, reflects a more significant outcome of the Arab uprisings. They have discovered that framing the turbulence as a sectarian conflict between Sunni and Shiite Muslims resonates not only with their followers, but with many outside Lebanon. And they are using the Syrian civil war as the cause célèbre to fight the case for what they see as discrimination against all Sunni Muslims. Assir openly accuses Hezbollah of crossing the border into Syria to kill Sunnis involved in the uprising against Assad.

"Our mission started in Saida (Sidon)," he told Now Lebanon, a popular website." But our movement is spreading in different areas. The numbers are increasing because of the pain of injustice."

Even if Assir fades from the spotlight, his direct affront to Hezbollah is producing two outcomes that are significant on a larger scale: He is magnifying feelings of injustice on both the Sunni and Shiite sides, and he is also provoking a response that makes it difficult for Hezbollah to continue to control its Lebanese constituency.

Hezbollah is a party and movement that is extremely disciplined and organized. The Shiite Lebanese attack on a television station in response to Assir, brings to question whether this is just the beginning of a street protest movement that will be outside the control of Hezbollah, which needs to maintain order as the most powerful faction within the Lebanese government. Similarly, if Assir is issuing directives, what does this say about the established Sunni leadership, or lack thereof? Over the last year, with Saad Hariri, the former Sunni prime minister, away from Lebanon in Paris, figures like Assir are moving in to fill the political vacuum.

As the Syrian war rages on, and is increasingly interpreted as a Sunni-Shiite conflict by those who wish to exploit it, there is little doubt Lebanon could be the first in a series of countries in the region to find sectarianism once again at its doorstep.

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