Partition of Iraq

In the years after the United States invaded Iraq in 2003, some people have said that they support the idea of partitioning Iraq, or dividing Iraq into three (or more) separate parts (a Sunni Arab part, a Shi'a Arab part, and a Kurdish part). These parts could be loosely united as an Iraqi federation or be three separate independent countries.
Support for this idea.
Support for the idea of dividing Iraq into three (or more) separate parts came from various prominent Americans and Iraqis, including Joe Biden, Leslie H. Gelb, Edward P. Joseph, Michael E. O'Hanlon, Khamis Khanjar, Atheel al-Nujaifi, Rafaa al-Issawi, Ali Khedery, John Bolton, and Michael J. Totten.
Criticism of this idea.
The idea of dividing Iraq has been criticized by Ben Connable. Connable said that none of Iraq's major groups or political factions actually want to divide Iraq and that neither do the Iraqi people. Connable also says that Iran (Iraq's most influential neighbor) does not want to see Iraq get divided and that the United States can't actually do anything to force Iraqi politicians to agree to divide their country into three (or more) separate parts. Connable also says that the new independent countries in the area will be unable to work together if Iraq is divided and that the violence and ethnic cleansing in a partitioned Iraq is likely to be even worse than it is right now. (In a separate article, Robert Mackey likewise argues that the idea of partitioning territories did not have a very good track record in Ireland, India, and Palestine and is thus unlikely to work very well in Iraq either.) Connable also doubts that an independent Shi'a Arab state in southern Iraq would actually want to share any of its oil revenues with a poor, landlocked, and backward independent Sunni Arab state in western Iraq.