Because the script was written referring not to Iraq as it was, but to a fantasy Iraq as Rumsfeld, Rice, and Bush et al. wanted it to be, or dreamt it to be, or were promised by their pet Iraqis-in-exile it would be. They expected to find a unified state like Japan in 1945. Instead, they found a perpetual civil war among majority Shi'a Arabs, minority Sunni Arabs, and Kurds. Saddam Hussein--a Sunni--had imposed a brutal peace on the country, but with him gone, the civil war reheated, and now it's ... erupted, and the CPA is embroiled. When you're in control, neutrality isn't possible.