Dubois worked for the "New York Herald Tribune" (1927–1929), before moving to Panama and working on various newspapers there. At the outbreak of World War II he became an army intelligence officer, serving in Panama, North Africa and Europe as well as the Pentagon. He was a graduate of the U.S. Army's command and general staff school at Fort Leavenworth. "TIME" described him as "an old friend" of Guatemalan President Carlos Castillo Armas, Armas having "studied under Colonel-Instructor Dubois during World War II in the U.S. Army's command and general staff school at Fort Leavenworth." Dubois was present during the 1954 Guatemalan coup d'état which brought Castillo Armas to power. His obituary declared that "he knew every president, every chief of staff, every dictator, and most of the would-be dictators in Latin America," and "could get more information on a telephone in a hotel room in one afternoon than most correspondents could get in months of travel."