ISIS's hardest fight and greatest challenges will come after they "win."

They will find that their state sponsors will shift their support to more moderate voices that are more likely to govern in a manner that is not a challenge to their interests.

They will find that many who either joined them or simply stood on the sidelines as they surged to push back current state control will form into discrete and active organizations with their own popular bases of support to compete for turf, influence or even dominance.

They may have to deal with a Shia based, Iranian backed counterattack that will come in a wide range of asymmetric and irregular forms. To include Shia foreign fighters from India and elsewhere who are every bit as motivated as the Sunni foreign fighters working with ISIS today.

The better governance the people hope for will likely elude them for a decade or a generation or two or three. It is a process.

Like the US learned in 03, ISIS will get the big strategic lesson learned - "winning" is the easy part.