A man shovel snow on the Yalu bridge, right, which destroyed during Korean War next to the Friendship Bridge linking between China and North Korea, in Dandong, China, Feb. 13, 2013. Defying U.N. warnings, North Korea on Tuesday conducted its third nuclear test in the remote, snowy northeast, taking a crucial step toward its goal of building a bomb small enough to be fitted on a missile capable of striking the United States. (AP Photo/Aritz Parra)