US warns of friendly fire as Iraq battlefield shrinks

MOSUL, Iraq — The day after Iraq’s prime minister declared an end to the Islamic State group’s caliphate, U.S. Army Col. Pat Work and a small team of about a dozen soldiers drove through western Mosul in two unmarked armored vehicles to warn Iraqi forces of a pressing threat: friendly fire.

The Mosul fight is the first time all three forces have had to cooperate in an urban environment and throughout the operation the army, federal police and special forces have faced deadly setbacks when they acted independently, allowing militants to concentrate their defenses on a single front.

Under the administration of President Trump, Defense Secretary Jim Mattis moved U.S. combat advisers closer to the fight by authorizing U.S. troops to partner with Iraqi forces at the battalion level.

The U.S.-led coalition’s fight against Islamic State in Iraq has slowly expanded over the past three years from a campaign of air strikes to an operation with some 6,000 American troops on the ground, many operating close to frontline fighting.