In order to damage the U.S. both economically and militarily, if war broke out between the U.S. and China would the Chinese attempt to disable the Panama Canal? The canal should be fairly easy to damage with land attack cruise missiles launched against either set of locks from ships off shore some distance. Failing that simply sending a ship through the canal with a large explosive device aboard to be detonated in one of the sets of locks (after the crew quickly abandons it) would probably be more than enough to disable one of the sets of locks. Note an attack doesn't have to destroy the canal or the locks for any length of time much less permanently. Just a few weeks duration would hurt U.S. trade and impede the ability of the U.S. to move major warships and support vessels from the Atlantic to the Pacific.