DuBose graduated with Bachelor of Science degree on June 7, 1913 and was commissioned Ensign on that date. He was subsequently assigned to the battleship and took part in naval blockade of Veracruz during Mexican Revolution in April and May 1914. The "Connecticut" then made a stop in Havana, Cuba and participated in the transport of Regiment of Marines and supplies to Haiti for U.S. occupation forces there. She then transported United States Ambassador to Haiti, Madison R. Smith to Port-au-Prince and remained patrolling in the near waters until December 1915.