The current conflict in Iraq is not religious in nature, it's a matter of who is going to control the central government. It's a question of if the country is going to remain as a single country or break up into three different countries. You have ISIS, the current government and the government of Iran as the central player.
The current conflict in Iraq is predominately about Islam or the Muslim faith. The faith split many years ago and created two groups the Shites and Sunni. America was aware of this problem far before we invaded and we knew that it would pop up eventually once we left. What we see now is the result of leaving a government that can not protect itself.
The majority of the groups leading the opposition fighting in the Middle East, claim that are doing so in the name of Islam, but the truth is that religion is only being used as an excuse and a way to grain power among the people of the lands they are trying to take over. It's the same story that has been played out in religious conflicts over time. It's not about the religion, it's about the power.
While from the outside it may look like it is about Islam and the different sects of the religion, ultimately it is about power. Islam is a peaceful religion and there are millions of people who are practicing Muslims who don't believe that what is going on in Iraq is anywhere near okay. Islam is an easy scapegoat that terrorists can use to promote their agenda.