Consequences of a US pullout from Iraq

King Abdullah of Saudi Arabia is concerned that, if the US pulls out of Iraq, the Shia dominated government might use Iraqi troops against the Sunni population. In that case, Saudi Arabia would back the Sunnis. One can speculate that Iran would respond strongly. The foreign policy issues of this should concern the next session of Congress except that, when it comes to Sunnis and Shia, congressmen don't know who's who.