Could it be some of the deaths were caused by the instability that toppling the existing Saddam Hussein government caused and not only by direct US military inv

Could it be some of the deaths were caused by the instability that toppling the existing Saddam Hussein government caused and not only by direct US military involvement? Some consequences that come to mind are warlords battling for control of provinces, unleashed tribal factions now free to kill each other, collateral damage from US military attacks destroying critical civilian infrastructure like sewage treatment and medical capacity, starvation, etc.