It is called Islam. Iraq is a micro portrait of the empire of Islam with every faction at each others throat and what is left over against the world. Bringing peace to Islam is like trying to train a dog pack to not eat cats.
I envision Iraq spitting into at least 3 separate countries before this is all over. "Democracy" can only be skin deep in a culture which embraces Sharia Law. We only fool ourselves by thinking otherwise.
Nonetheless, we are doing the correct thing by being there and advancing our own interests.