Iraqi troops train for their assault on the northern Iraqi city of Mosul, currently under the control of the Islamic State, on Jan. 10. (Safin Hamed/AFP/Getty Images)

The Obama administration has touted the modest successes in recent months of Iraqi forces and paramilitary fighters, backed by U.S. air power, as they have fought to wrest towns, villages and parts of Iraq’s rugged countryside from the Islamic State.

Now, the renewed U.S. campaign in Iraq faces a greater challenge as American advisers scramble to prepare Iraqi forces for an offensive to reclaim some of Iraq’s most important cities, which remain under the militant group’s control.

Attempting to take back the city of Mosul, the country’s ­second-largest, as well as Tikrit and Fallujah, will test not only the fighting power of Iraqi forces and the country’s fragile sectarian compact but also President Obama’s indirect strategy for containing the Islamic State.

A U.S. official in Baghdad, who like others spoke on the condition of anonymity to discuss the evolving campaign, said the United States and a coalition of Arab and other allies are “on a steady progression of effectiveness” in six months of airstrikes against the Islamic State.

“To win this thing, we’re going to have to have Iraqi ground troops go into the places that are really being held by Daesh,” the official said, using the Arabic name for the militant group. “You’re not going to win this just with airstrikes.”

Kurdish Peshmerga fighters inspect an rocket-propelled grenade launcher as they take control of the area, on the outskirts of Mosul, February 6, 2015. (Stringer/Iraq/Reuters)

The Islamic State easily captured Mosul last June after Iraqi soldiers abandoned their posts in droves. The rise of the militant group led to a change of government in Baghdad and galvanized an international coalition to support Iraqi forces with airstrikes.

The fighting that followed — between the well-armed militants on one side and a mix of Iraqi forces, Kurdish peshmerga, Shiite militiamen and volunteers on the other — has taken place mainly outside Iraq’s largest cities.

Some fighting has occurred in urban areas. Ramadi, the capital of Anbar province, and Baiji, a small city that is home to an oil refinery, remain contested. Government forces control areas on the edges of Tikrit but have not been able to seize the city.

“We’re very aware of how big of a symbol it would be to be able to take back one of these major operating areas from” the Islamic State, said another U.S. official. “But we certainly don’t want to have the Iraqis go into those types of fight without the proper organizational structure, without the resources needed, such that they’ll succeed.”

U.S. officials plan to help Iraq prepare by providing soldiers from some of the country’s best military units with enhanced training in skills they will need in an urban setting: house-to-house fighting, handling improvised bombs, identifying booby traps and protecting against sniper fire. Ordinary obstacles such as narrow streets or low-hanging power lines make it harder for tanks and soldiers to maneuver.

Sending soldiers into Iraq’s chaotic cityscapes to root out adversaries is painstaking work, requiring precision as troops progressively clear tightly populated areas and identify targets for air or artillery attacks.

“The difference between the open, rural context and the urban context is night and day,” said Nate Freier, a researcher at the Army War College who served twice in Iraq, “especially if you’re talking about close-in operations, where threats are . . . right around corners and you really don’t know they’re there until you get to them.”


While U.S. forces honed those skills during the last Iraq war, the Iraqi military, which was rebuilt from scratch after 2003, has much less experience in urban fighting, said retired Army Lt. Gen. Frank Helmick, who commanded the U.S. effort to train Iraqi forces in 2008 and 2009. He said the goal of that training was largely to build up security institutions and train Iraq’s conventional army in external defense.

“Urban fighting is going city to city, street to street, building to building, room to room,” Helmick said. “Our goal was to get the army out of the cities in order to allow them to help secure the borders.”

In general, said Ahmed Ali, a senior fellow at the Education for Peace in Iraq Center, “this was not part of their mandate, and they were heavily reliant on U.S forces to engage in urban battles from 2004 to 2008.”

The same will not be true in 2015. Obama, intent on limiting U.S. involvement in Middle Eastern conflicts, has ruled out sending U.S. troops into combat. That will make the performance of Iraqi forces critical to his plan to indirectly battle the Islamic State.

The biggest test promises to be Mosul, which became a hotbed for the Sunni insurgency after 2003. Many of the city’s residents have fled, and those who remain live under the Islamic State’s austere rule. As militants prepare for an offensive expected to begin as early as this spring, the group is hardening its defenses in the city.

“Mosul is simply going to be hard,” said Jessica Lewis McFate, a former Army intelligence officer at the Institute for the Study of War, especially if militants try to draw attacking forces into the city “and sink them” there.

“It’s going to be a difficult fight,” said a U.S. defense official. “It’s important that when [Iraqi forces] do it, it’s a decisive fight.”

U.S. officials say no decisions have been made about the timing of an attempt to recapture Mosul or other cities, or about the makeup of the force that will be sent there.

The sensitivity of the latter question underscores the delicate position of Prime Minister Haider al-Abadi. Much of the heavy fighting against the Islamic State has been done by Kurdish peshmerga forces and Iranian-backed Shiite militias and volunteers. But deploying Kurdish or Shiite fighters into largely Sunni Arab Mosul would be a risky move, potentially undermining any local support for the operation. In recent weeks, Iraq has been gripped by reports that militiamen have carried out sectarian killings.

An official from Iraq’s Defense Ministry said the government was reluctant to send militias into Mosul because of “fear of the reaction of the people . . . who reject the policy of Iranian interference.” Mosul residents might also oppose the entry of peshmerga fighters whose long-standing mission has been protecting the largely autonomous Kurdish region.

Sheik Ahmed Abu Risha, a prominent Sunni tribal leader from Anbar province, said reliance on militias would open the door to abuses and trigger renewed sectarian fighting among Iraqis. “We want the fight to be against ISIS only,” he said, using an acronym for the Islamic State.

Those sectarian hazards will be equally present in Tikrit, the birthplace of Sunni Arab strongman Saddam Hussein, and Fallujah, where resentment toward the Shiite-led government in Baghdad has helped keep the city in Islamic State hands for more than a year.

Urban offensives may require a shift in U.S. air tactics as well. Because dropping bombs on a major city would increase the odds of striking civilians, U.S. military officials may request White House permission to send air controllers closer to the front lines.

Abu Risha said a first step should be clearing Fallujah, Ramadi and all of Anbar in order to weaken the group in Mosul and in Salahuddin province, where Tikrit is located.

“The fighter’s wisdom says you should strike the weak first,” he said, “so you instill fear in those that are still strong.”

Salim reported from Baghdad.