American intelligence agencies and the Pentagon are struggling to determine how difficult it will be to retake Mosul, Daesh’s de facto capital in Iraq, as planning intensifies for a battle that is becoming a major test of the Obama administration’s strategy to stop the spread of the terrorist group in the Middle East, the New York Times reported on Sunday.
The assessment will be pivotal in driving important policy and military decisions that President Obama will need to make in the coming weeks, including whether the Pentagon will need to deploy teams of American ground forces to call in allied airstrikes and advise Iraqi troops on the battlefield on the challenges of urban warfare.
Reclaiming Mosul, which has a population of more than one million people and is Iraq’s second-largest city, will require 20,000 to 25,000 Iraqi and Kurdish forces to clear it block by block, with many of the streets and buildings likely to be rigged with explosives, American officials said. The battle is planned for as early as April.
The city is being held by 1,000 to 2,000 Islamic State militants, according to United States military estimates. It sits astride one of the major infiltration routes that Daesh has used to ferry troops and supplies into northern Iraq from Syria.
American intelligence agencies say they do not yet know whether Daesh fighters will dig in and defend Mosul to the death or whether, fearing encirclement, most fighters will slip out of the city for other Iraqi towns or cross the border into Syria, leaving behind a smaller force and booby-trapping buildings with bombs to tie down and bloody thousands of Iraqi troops.
In preparation for the assault on Mosul, the United States and its allies are trying to weaken Daesh by cutting its supply lines. Kurdish forces, backed by American-led air power, have recently positioned themselves near an important crossroads at Kiske, 25 miles west of Mosul. “The isolation of Mosul is going on now,” said the official at Central Command.
In addition, American officials took the unusual step on Thursday of announcing the timing of the battle and the number of Iraqi and Kurdish forces to be deployed. Openly discussing future military operations is normally off-limits to avoid aiding the enemy, but American officials said it was done this time to try to weaken the resolve of Daesh fighters and to spur Mosul’s residents to rise up against the occupiers and help the Iraqi ground forces.
Another challenge will come if the city is retaken. While Mosul is overwhelmingly Sunni, the Iraqi attacking force is likely to be overwhelming Shiite, which may create friction with the local population. The Sunni Arab population could be alienated if their neighborhoods were held by Shiite-dominated units or Peshmerga forces.
The plan calls for introducing a stabilizing force that would be composed of former Mosul police officers and Sunni tribal fighters. But it is unclear how synchronized this effort will be.