The President of the United States of America takes pride in presenting the Navy and Marine Corps Medal (Posthumously) to Lieutenant James S. Clarkson, United States Navy, for heroic conduct as a volunteer diver engaged in Pearl Harbor salvage operations following the Japanese attack on 7 December 1941. Lieutenant Clarkson unhesitatingly made many hazardous dives in essential underwater work and by his tireless efforts contributed greatly to the success of the salvage operations.