After graduating from Marshalltown High School in 1902, Fletcher attended and graduated from the U.S. Naval Academy at Annapolis, Class of 1906. He was the nephew of Vera Cruz commander and MOH recipient Frank F. Fletcher. During World War I he received the Navy Cross as commander of the U.S.S. Benham. He graduated from the Naval War College in 1930 and the U.S. War College in 1931. In World War II he was second in command to Vice Admiral Halsey in the Marshall and Gilbert Island raids of 1942. Retiring as an Admiral in the U.S. Navy, he achieved the highest rank of any MOH recipient from the State of Iowa.