The U.S. nuclear-powered aircraft carrier USS George Washington (down) and the Arleigh Burke-class guided missile destroyer USS McCampbell (up) leave for joint naval and air drills with South Korea at a naval port in Busan, South Korea, July 25, 2010. South Korea and the United States on Sunday began their large-scale joint military drills off the east coast of the Korean Peninsula as scheduled. (Xinhua/Yonhap)