Gotta say, this has been one of the better threads I've read anywhere.

In Democracy in America, De Tocqueville prognosticated that the United States would not survive for long because of the many small interests competing in the country. As it turns out, America has probably survived for as long as it has because of those many conflicting special interests. They have prevented the nation's being overwhelmed by a tyranny of the majority. Contrast our country’s relatively peaceful internal disagreements with the struggle in Iraq between Shia (empowered majority) and Sunni (largely disempowered minority). Attribution of the conflict to religious differences is, I believe, largely a misapprehension of the social dynamic--conflict is almost always about power.
Note that we cannot forget our own history here. A mere 25 years after de Tocqueville published, the U.S. fought a rather massive civil war that was, so far, much bloodier than what has gone on in Iraq (assuming you do not subscribe to the Lancet). The aftermath of this featured decades of racial terrorism against African-Americans throughout the South. I trust that the history of Native Americans does not have to be rehashed here as well - let us just note that Phil Sheridan would not have had many quibbles with Ali Hassan al-Majid in his methods in crushing uppity natives.