The United States forces in Iraq believe that Islamic State will likely use chemical weapons when it defend its stronghold on the city of Mosul from coalition forces led by Iraqis.  U.S. officials, however, expressed doubts on the technical capabilities of ISIL to manufacture chemical weapons.

American forces have started to scour for shell fragments to determine which chemicals are likely to be used in the forthcoming assault to retake Mosul, a city ISIL has occupied and committed to defend. . Islamic State has been known to employ mustard agents in previous skirmishes in Iraq.

One official believed that Islamic State will use a type of sulfur mustard agent since residues of this deadly chemical have been found at places where they engaged against local troops. This only shows the propensity of ISIL to disregard international rules of engagement.  

So far, conventional weapons remain to be main threat against local and coalition forces poise to retake the city of Mosul. There have been no incidents where chemical weapons have been employedwith lethal effect against either Iraqi or coalition forces.

Out of more than 5,000 U.S. forces deployed in Iraq, only about 100 are operating with Iraqi and Kurdish forces involved in the assault of Mosul. They are not at the battle front lines but are assigned to help direct coalition air power to the right targets.

While the recapture of Mosul is a strategic victory for the coalition against ISIL in Iraq, there is lingering fear that land grabs and sectarian bloodbath will be repeated, just like what happened in the battles of 2003 when Saddam Hussein was overthrown.

President emphasized that with an estimated one million civilians in Mosul, the Iraqi and coalition forces must not only expel the Islamic State from Mosul but also protect the civilians fleeing from the battle zones. This will ensure that ISIL forces cannot recover from their impending expulsion.