ISIS look like they create a decentralized Jihad situation which is spread in several countries and territories. So defeating them will not be easy as it was with any former extreme group. ISIS will not be defeated by bombing Syria with air craft
ISIS is too extreme and the Leaders don't care about innocent people dying just they are encouraging poor,innocent people to fight on the name of religion.
Not for the US army. They will level oil fields, refineries, roads, bridges, Daesh gov buildings, power stations, TV, cell towers, freeze their bank accounts, cut the Internet access. Then they will destroy their trucks, Humvees, construction equipment, supply warehouses, destroy water processing plants.
I'm sure West-point guys have plans ready to go. They don't even have to have boots on the ground.
Daesh is on the express train to stone age.