Please define who the civil war will be between.   Is it the Shiites vs the Kurds? Or is it the Iraq govt vs the terrorists such as Al Sadr?   Or is it a fight over who runs the Iraq government?

The USA had a civil war and it ended slavery.   Despite the large number of people killed, that was probably a worthwhile outcome.   It also changed the hearts and minds.   No sane person supports slavery in the USA today- even in southern states who fought to preserve it.

Iraq must find its own way whether they will become a demoncarcy, a dictatorial governement or a terrorist state.    At least they have hope.   With Sadaam there was no hope.   If Libyia can denounce terrorism, there is hope that Iraq can do the same.