Islamic State: In Iraqi battle for Tikrit, signs of Iran's expanding role

US officials worry that Iran's major role in the fight against IS in Iraq could fuel Shiite-Sunni tensions and drive more Sunni Arabs into the arms of the jihadis.

In this image made from video, smoke rises from an explosion as Iraqi forces, Shiite militiamen and Sunni tribal fighters battle Islamic State militants for control of Tikrit, Iraq, Tuesday, March 3, 2015. Backed by Shiite militias and Sunni tribal fighters as well as Iranian advisers, the government forces made little progress on the second day of a large-scale military operation to recapture Tikrit, which fell to the Islamic State group last summer, two local officials said.

AP Photo via AP video

March 3, 2015

The Iranian military is reportedly playing a significant role in Iraq’s latest push to retake the city of Tikrit from the self-described Islamic State.

Unnamed US officials told the Wall Street Journal that Iran is supplying artillery, rockets, and aerial drones for the offensive. A commander of Iran's Revolutionary Guards is also taking part.

Iran and Iraq have grown close since the the US-led 2003 overthrow of Saddam Hussein. While Saddam was a staunch enemy of the Islamic Republic, many of the Shiite politicians who came to power in the wake of the invasion were financed and protected by Tehran while living in exile. Military cooperation, both formal and informal in the guise of the country's major Shiite militias, has deepened over the past decade, a process that's accelerated since IS captured the northern city of Mosul last June. 

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Still, American military and other government officials are wary of the Iranian support for Baghdad. Both countries have Shiite majorities, and the US fears a rekindling of sectarian violence between Iraq's Shiites and Sunnis.

“To the degree they can carry out an offensive without inflaming sectarian tension and can dislocate ISIL, it can be helpful,” a US official told the Wall Street Journal, using the US government's preferred acronym for IS.

Iranian Gen. Qasem Soleimani, the commander of the Revolutionary Guard’s elite Quds Force, is helping Iraqi forces in the assault on Tikrit, Saddam Hussein's hometown. The BBC reports that Gen. Soleimani has emerged as a chief tactician in Iraq's fight against IS. Since IS advanced across Iraq last summer, he’s personally overseen the defense of Baghdad and helped to organize pro-Iranian Shiite militias.

This isn’t the first time Iran has assisted Iraq in its fight against IS. It previously carried out airstrikes within the country and sent advisers to help retake a Sunni town outside Baghdad. But, according to US officials, the Tikrit fight represents the greatest level of support yet for an Iraqi offensive.

The operation is seen as a test of the capability of Iraqi troops and represents a strategic target. Tikrit lies on the road to Mosul, Iraq's second largest city, which the Iraqi military plans to push for next. As Reuters reports:

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The Tikrit battle will have a major impact on plans to move further north and recapture Mosul, the largest city under Islamic State rule.

If the offensive stalls, it will complicate and delay a move on Mosul. A quick victory would give Baghdad momentum, but any retribution against local Sunnis would imperil efforts to win over Mosul's mainly Sunni population.

US officials expect the Mosul offensive to begin in April or May. Iraq’s military is expected to commit 20,000 to 25,000 troops to the operation.

For now, US officials worry that Iran’s involvement in Tikrit could have unintended consequences. They have frequently cautioned Iran to tread carefully in Iraq to avoid reigniting a religious-based civil war. The Associated Press reports:

If marauding Shiite militias enter Tikrit, they could drive Sunnis back into the hands of the Islamic State, since Sunni leaders oppose the militias. The operation also poses the risk of high civilian casualties because Iraqi and Iranian forces have not been as precise as US forces in using air power against the militants.

The US-led air coalition has yet to participate in the Tikrit offensive, Reuters reports, possibly in part because of the Iranian presence. The State Department's Brett McGurk, Obama's envoy to the coalition fighting IS, wrote yesterday of "multiple offensives" taking place in Sinjar, Baghdadi in Anbar province, and Tikrit and that the operations are "enabled either directly or indirectly by the coalition air campaign, which has significantly degraded ISIL's capacity."

Iraq launched the operation to reclaim Tikrit on Monday and announced the deployment of some 30,000 troops. On Tuesday, Iraqi government forces said they had retaken some districts around the city.