The costs associated with devolving Iraq into three semiautonomous regions with loose central control would be too high. Because Iraq’s population is not neatly separated, regional boundaries cannot be easily drawn. All eighteen Iraqi provinces have mixed populations, as do Baghdad and most other major cities in Iraq. A rapid devolution could result in mass population movements, collapse of the Iraqi security forces, strengthening of militias, ethnic cleansing, destabilization of neighboring states, or attempts by neighboring states to dominate Iraqi regions. Iraqis, particularly Sunni Arabs, told us that such a division would confirm wider fears across the Arab world that the United States invaded Iraq to weaken a strong Arab state.