Joseph Cruz, Jr. entered the military service in New York. He served in the United States Naval Reserve as a Motor Machinist's Mate 3rd Class during World War II. He was aboard the USS LST 531 and was killed during the Exercise Tiger--one of the large-scale rehearsals for the D-Day invasion of Normandy. This took place in April 1944 in Slapton Sands, Devon in the UK. An Allied naval convoy involved in the exercise was attacked by German submarines, and coordination and communication problems resulted in friendly fire deaths. At least 749 American servicemen were killed. Because of the impending invasion of Normandy, the incident was highly classified and the full story did not come out until years later after the war. MoMM3 Cruz was declared "Missing in Action" on April 29, 1945 and his name is memorialized on the Tablets of the Missing, Normandy American Cemetery, Colleville-sur-Mer, France. He also has a cenotaph located in Long Island National Cemetery, East Farmingdale, Suffolk County, New York, USA.