The complex military operation to seize Iraq’s second city from ISIS’s grip is a microcosm of the long war.
The Syrian city of Raqqa is regarded as the operational headquarters of ISIS. But Mosul, the second city of Iraq, is far more populous. And ISIS’s rapid expansion from 2013 culminated there, when Abu Bakr al-Baghdadi declared the existence of an Islamic caliphate in Mosul’s chief mosque on 4 July 2014.
ISIS propaganda greeted this event as the distinguishing feature of its whole movement. The announcement, the violence of the movement’s expansion across northern Iraq that preceded it, and the strong western response, together led to the western air-war that started the following month (see “ISIS against, and in, the west”, 22 September 2016).