It is time for Iraq to stand on its own -- without a U.S. presence to disrupt its politics. There are significant factions within both Iraq's Kurdish and Sunni communities that would look favorably on a residual U.S. force in Iraq. They need to move on. The lingering U.S. troop presence on Iraqi soil is -- quite understandably -- perceived as an insult to Iraqi nationalism by significant portions of their fellow citizens. This is an issue that must be taken off the table so that Iraqi politics can normalize, not least with regard to Iraq-Iran relations. Ironically, it is by leaving Iraq that the United States can best let Iraq stand up to its Iranian neighbor. Ending what Iraq's neighbors perceive as its "occupation" by U.S. forces will finally permit Iraq to complete the normalization of regional relationships.