Butler, during his Regular Army tour, served in the U.S. Army Security Agency's Special Operations Unit and later with a U.S. Army Reserve Combat Engineer Battalion. In April 1975 he was commissioned Captain in the Massachusetts State Guard. He was the former Curator of Fort Warren and Fort Independence, Boston Harbor, and Fort Rodman in New Bedford, Massachusetts. He serves as consultant to military historical organizations, museums, state parks, lectures, was the former historian for U.S. Navy mine units in Boston and Portsmouth Harbors, and his cartoons and illustrations of seacoast fort...