Yes, for long-term goals there is an alternative. In fact, the only option we have, which is going to be the best option, is bringing these sides together under the United Nations' supervision and having them work together. They may not agree. This is only an opinion, my opinion: secure the borders along these countries around Iraq and have the army do the defence, as usual, and not have the army do the policing job.
Religion, just like freedom, can be used, but cannot be abused. Once you overdose on any kind of medication, it might harm your life, and it's the same thing with religion. People who are overusing it need to be educated and taught how to properly use it. In fact, in Iraq in particular, that's one of the biggest issues since 2003. Religion has dominated the area and become pretty much the main dominance, replacing politics. Religion cannot be used in this room to discuss as politics, but can be used in a church or a mosque to talk about peace, and not used as a tool or weapon to encourage people who don't know anything about the outside world and use it to harm and hurt people, especially innocent minorities.