Having spent 25 years living in the Middle East, and having a father
immersed in Middle East behind the scenes political intrigue first as CIA and later as consultant, one thing was always clear;
The religious/tribal divide is the elephant in the room that there is no easy way around.
In fact the only way around it has been by force of a strong dictator or foreign power. The elimination of the strong dictator in Iraq, Libya, Egypt and the attempt in Syria has led to obvious results. US forces acted as a force and removal has likewise led to obvious results. It is surprising therefore that when political analysts and pundits discuss the region they avoid the obvious and say things like we should work to "prevent the breakup of Iraq along ethnic grounds".
We accepted the inevitable breakup along ethnic lines in Yugoslavia after the death of strongman Tito. We accepted it in Sudan which broke into two nations along religious and ethnic grounds. We accepted the division of Czechoslovakia into two states along ethnic grounds. We even accepted the possibility of Scotland leaving the United Kingdom if they had voted for succession.
Of course, though we don't like to say it, we accepted the concept of a state entirely based on religious/ethnic grounds when we accepted the independence of Israel which unabashedly calls itself "the Jewish state.
So why do we insist on Iraq being one country when it was the creation of a silly plan drawn up by ignorant Europeans after World War I? Iraq and Syria are creations that have inherent conflicts and divides that should once and for all be faced. For starters, the Kurds should finally get a state. Then divide the Shea and Sunni areas and the elephant will shrink into a mouse. Trying to hold these non states together without a strongman will ALWAYS require international peacekeepers which to all intents and purposes means the US. We Americans should not see our tax Dollars wasted nor our boys die to keep people who don't get along together in one state especially when they are prepared to fight for the separation.
The history of Europe has shown that eventually different sides can come to the conclusion that some sort of unity is not a bad thing and if the Middle East countries made more geographic sense they would very possibly do what Europe did with the EEC given time. Forcing them to work together is a fools errand and its about time we faced up to it.