Iraq Prime Minister Haider al-Abadi announced Monday the final phase of the offensive to retake Mosul, Iraq’s second largest city. Here are some key questions and answers:
How important is the battle?
Mosul is the most critical battle to date in the campaign to drive the Islamic State from Iraq. It is Iraq’s second largest city and was captured by militants more than two years ago. Driving the militants from the city will mean the end of the Islamic State’s self-declared caliphate in Iraq.
What are the main challenges?
Urban fighting is the most challenging type of warfare for ground units. It requires highly disciplined and trained soldiers because the fighting is complex. Junior leaders need to be able to make decisions on their own and soldiers have to withhold fire if civilians are endangered. The close-in street fighting makes it difficult to use coalition airstrikes and artillery. There are an estimated one million civilians in Mosul and the Islamic State frequently uses human shields.
How many militants are in Mosul and how many Iraqi forces will be involved in the operation?
The Pentagon estimates there are between 3,000 and 4,500 militants in the city. They are of varying levels of commitment. But several hundred will probably elect to fight and die. Others will likely flee. The militants have had years to build elaborate defenses, including tunnels and booby traps. The main Iraqi attack force will consist of about 12 U.S.-trained brigades, more than 30,000 troops. Loyal tribal and self-defense units will also be used to provide security once the militants have been expelled from the city.
Are Americans involved?
U.S. advisers are at the headquarters level in a number of Iraqi units, though they do not accompany Iraqi troops into battle. U.S.-led coalition troops have trained all the Iraqi brigades that will be involved in the operation. Coalition airstrikes have ramped up targets in Mosul in recent months as Iraqi forces began moving to surround the city and prepare for the final assault.
How long will it take?
There are too many variables in warfare to make reliable predictions, but the fighting is sure to be slow and may take weeks or months. Even if militants attempt to flee the city, the elaborate booby traps and other obstacles have to be carefully and methodically dismantled.
What happens next?
The Islamic State has been increasingly turning to terror tactics – bombings and assassinations – in the region and around the world, even as it has lost territory. The loss of the Islamic State’s self-proclaimed caliphate, however, will hurt the militants ability to recruit and will liberate hundreds of thousands of people from under its yoke. Many of the sectarian tensions that gave rise to the Islamic State still exist in Iraq, which could make stabilizing cities like Mosul difficult and could lead to further violence.