With the departure of the 4th Stryker Brigade, 2nd Infantry Division, all United States combat troops have now left Iraq. However, with 50,000 U.S. troops still in the country for training purposes, American liberals remain suspicious of whether this milestone is worth celebrating -- or whether the final departure date for all U.S. troops in December of 2011 should be taken seriously. Meanwhile, there's an impending uptick in private security forces to fret over.