Pith & Substance endorses Fred Kaplan's plan for Iraq. The most useful thing the US military could do while it is waiting for the inevitable order to withdraw would be to help Sunnis in Shi'ite-majority areas move to Sunni-majority areas. And vice versa and mutatis mutandis. If it cares either about morality or its future influence, America ought also to do something about the security of those stupid enough to cooperate with it: Kurdistan gets its borders guaranteed and all the translators and so on currently hiding out in Jordan or Syria get green cards.
Not going to happen so long as the Republicans control the White House. The only hope for relatively humane ethnic cleansing lies in the party of Jefferson and Jackson.