The President of the United States of America takes pride in presenting the Navy Cross (Posthumously) to Sergeant Joseph D. Sheehan (MCSN: 310043), United States Marine Corps, for extraordinary heroism and devotion to duty while serving with the First Engineer Battalion, FIRST Marine Division, in action against enemy Japanese forces on Peleliu Island in the Palau Group, on 4 October 1944. Vigorously supporting the advance of a friendly company, Sergeant Sheehan led his demolition squad with furious aggressiveness. When the enemy hurled the full force of their huge gun-batteries against the onrushing Marines and held them up with the merciless enfilade fire of one cave-emplaced machine gun which struck down forty-two of the forty-six men in the advancing unit and forced a temporary withdrawal, he fearlessly pushed on alone despite the ceaseless pounding of the heavy Japanese weapons. With the hostile cave as his objective, he relentlessly worked his way forward and, reaching his goal, dropped a powerful demolition charge into the Japanese position, destroying the valuable machine gun and annihilating the entire gun crew. By his intrepid initiative, resolute fortitude and decisive action in a critical situation, Sergeant Sheehan contributed essentially to the final crushing of a ruthless and fanatic enemy, and his great personal valor and unwavering devotion to duty throughout reflect the highest credit upon himself and upon the United States Naval Service.