If we were willing to inflict massive collateral damage, we could discourage ISIS and its imitators for a long time simply by bombing. This is the lesson of Hama, Syria. In 1982, Hafez al Assad put down a Sunni Muslim insurgency centered in the town by surrounding it and then shelling it for 3 weeks. The place was leveled. Between 10,000 and 25,000 people were killed in the fighting. Things got quiet for almost thirty years. The US Air Force has the physical power to do that kind of damage to ISIS' capital in a week. We don't have the capability to do it morally. That's why we need boots on the ground to completely defeat ISIS.
Without boots on the ground, we can "win" only in the way the Israelis win. They call their periodic wars against Hamas and Hezbollah "mowing the lawn." The weakness of Hamas, Hezbollah and ISIS is all the same. Once you claim and hold real estate, you become responsible for what happens to it. In Lebanon in 2006 and in Gaza this year, the Israeli Air Force was very, very destructive. The damage estimate for Gaza is $6 billion. The damage to Hezbollah assets, along with Lebanese infrastructure and Shiite owned or occupied buildings, was similarly massive. Hezbollah has not really attacked Israel since. I think it's because even though the Iranians paid for a lot of rebuilding, they can't afford to do it again. Hamas is finding that Gaza residents are equally unhappy with the massive damage that may take a decade or two to repair. ISIS is similarly vulnerable. They own territory with assets they value. If those assets vanish in a series of targeted explosions, leaving worthless rubble, they will lose the ability to buy support.
Our first strikes against ISIS in Syria were disappointing. It’s an indication of how much we want to avoid collateral damage that we blew the antenna array off of an ISIS building without blowing the building up. We only destroyed the antennas on the ISIS financial control center, leaving the building intact with all the computers and equipment used to manage ISIS' money. We should have destroyed everything to make it harder for ISIS to manage its funding. A 2,000 lbs. guided bomb would have taken the whole thing down. This smells like a civilian designed targeting order. It really seems like the White House is drawing up what the targets are and how hard we are going to hit them. Do we want to "send a message" or do we want to destroy or at least degrade ISIS?