The ISIS attacks were “enough to make the Iraqis believe they didn’t want to fight,” a defense official told The Daily Beast. “We’re still trying to figure out what flipped the switch.”

There are differences between how the Iraqi troops performed in Mosul and Ramadi, U.S. defense officials said. Iraqi forces held the city for more than a year, even as ISIS-controlled areas dominated the province. And while Iraqi troops stationed in Mosul last year were wearing civilian clothes under their uniforms, in Ramadi, they conducted a tactical retreat.

That said, they were a broken force—when they were supposed to be a keystone of the U.S. strategy in Iraq. Instead, the strong local ground force that the Pentagon hoped could exploit American air superiority over ISIS does not appear to exist within the Iraqi army.