The really tragic thing about all this is that in a few years, after many have died and lives have been changed negatively forever, these factions will decide to live in some semblence of peace. Why not do it today and spare the heartache?
Course I could be wrong, they may conduct themselves like rodents in perpetuity.
The different factions are getting sorted out. Maybe an alliance between Kurds and Sunni Arabs to prvent a Shiite government from exclusing them. The Kurds also have oil, which gives them a strong card. But the matter is really more complicated, since tribal interests have to be factored in.