November 9, 2016
It is natural for most reporting and military analysis to focus on every major development in the daily fighting against ISIS, but the fight to liberate Mosul and Raqqa is only one part of a much longer and more complicated struggle that may well go on for years. While some in the White House staff do talk of "victory" in Mosul—and even Raqqa—before President Obama leaves office, virtually no one actually involved in shaping U.S. and Iraqi strategy believes this is possible. The main body of ISIS forces in Mosul may be defeated, but this will only be a prelude to what will be a different and much longer fight.
Senior U.S. officers and officials have warned publicly for months that clearing Mosul is likely to be followed by a long period of fighting with elements of ISIS that have dispersed into the Iraqi countryside, hidden in the city, and/or stage out of Syria. They have made it clear that unless ISIS actually collapses, Iraqi security forces are going to have to secure the city over a long period of time, and will have to do so at a time when Iraq will be seeking to return internally displaced persons (IDPs) to Mosul and other cities and villages in western Iraq, and to rebuild these cities and villages. U.S. officials have warned that some ISIS fighters may disperse to other countries and carry out acts of terrorism, but that other ISIS fighters will try to attack targets throughout Iraq—and that such attacks are already underway.
It is equally clear that the fight against ISIS in Mosul and Iraq cannot be separated from the fight against ISIS in Raqqa and Syria. The long border between Syria and Iraq is almost impossible to secure against infiltrators, and there are many routes that are relatively easy to use to smuggle in arms and even heavy weapons. The greater the freedom ISIS has in operating out of Syria, the greater the challenge to liberating Mosul and the rest of Iraq, as well as to any effort to create a Syrian rebel presence that will not be tied to other extremist movements, and that can check or contain the pro-Assad forces.