The successful liberation of Fallujah from the Islamic State by a constellation of Iraqi forces in June provides pointers for the more challenging mission of liberating the much larger city of Mosul. Relatively efective coordination of Iraqi forces, coalition airpower, and vital intelligence from Sunni tribes and townspeople led to the Islamic State being driven out more quickly than expected, despite the fact that an unauthorized incursion by Shi`a militias risked compromising the ofensive, as well as attempts to secure and rebuild the town. Mosul will be harder to take because Islamic State fighters are less likely to flee in large numbers. It may be possible to make significant progress in the coming weeks because of weakening Islamic State capabilities and morale and the emergence of resistance forces
in the city providing key intelligence, as well as successful cooperation so far between Baghdad and Erbil. But the large number of rival Iraqi actors and regional powers— particularly Iran and Turkey—jockeying for position in Mosul means that unless their conflicting agendas can be resolved, any victory in securing the city could be fleeting.