They look similiar to you. There are numerous cases ranging from Eastern Europe to Africa where different ethnic groups that most would consider similiar looking and probably of the same gene pool saw differences. When you are in the ethnic group in question, the differences are real and matter to you. For instance, I cannot tell the difference from one asian ethnicity to another. I simply can't, nor am I good at determing the differences between hispanic groups....they can tell the differences. These differences are very real to them.
As for naming a democracy that doesn't alienate it's people, that would be imposible. At the same time, it's not exactly something that those democracies promote. The United States suffered dearly for alienating its African-American population in the 60s, along with it's population of women at around the same time period. Following that were the protests of homsexuals. The Great Depression almost resulted in a socialist revolution in the United States, to the point of social welfare programs being put in place to find a compromise, coming from the alienation of the poor. While no country perfectly blends its citizens together, they at least make an effort to do so. The new Iraqi government not only didn't do this, it tore the groups apart.
Yes, the Iraqi conflict is indeed an example of hubris. We came in wanting to bring democracy to the world, our government is obviously the supreme form and they would herald us in. Take out the dictator and give these people what they must want, our government. Do this also while telling the rest of the world to kiss our butts and mind their own buisness.