Twenty-one years ago, the U.S. and its allies invaded Iraq in the erroneous belief that the country possessed weapons of mass destruction and was allied with al-Qaida, the terror group responsible for the 9/11 attacks. The U.S. created an occupation authority, but failed to restore order and helped spawn the insurgency that bedeviled it by dismissing the entire Iraqi military and the most experienced civil servants. Coalition troops fought a losing battle, regained their footing with the 2007 troop surge, and finally departed in 2011. U.S. troops…
