 Upon the graduation, he was assigned to the 2nd Cavalry Regiment at Fort Riley, Kansas and served as Regimental Executive Officer until April 1941, when he succeeded another brilliant equestrian, Harry Chamberlin in command of the regiment.Cole was promoted to the rank of Colonel at that time.Following the United States entry into World War II, Cole was transferred to the Armored Force in July 1942 and assigned to the 5th Armored Division that October.