President Obama announced Wednesday that he has accepted Gen. Stanley McChrystal's resignation as the commander of U.S. forces in Afghanistan following a scathing article in which he and his aides were quoted criticizing the administration for its handling of the war. In doing so, Obama nominated Gen. David Petraeus, the head of U.S. Central Command and the former commanding general in Iraq, to replace him. The president stressed that while the decision was a difficult one, it does not represent a change in the course of the war. "This is a change in personnel, but it is not a change...