And then there's the refugee problem

Of the thousands of Kurds who Saddam displaced from their homes around Kirkuk as part of his "arabization" policy, and who now want to reclaim their homes, displacing thousands of arabs; and the thousands of Shiites in the south whom Saddam "relocated" after the Gulf War, who are also returning to their homes.
When these factions clash, what will our forces do? Watch?