舞鶴鎮守府
Suetsugu subsequently served on the Japanese delegation to the Washington Naval Treaty negotiations in 1921, although he was a prominent member of the Fleet Faction. During his period in staff assignments at the Imperial Japanese Navy General Staff, he worked on revisions to the Japanese battle plans and strategies, especially targeting the United States Navy, and to opposing the efforts of the Treaty Faction, especially after the signing of the London Naval Treaty. He was promoted to rear admiral in 1923 and vice admiral in 1927. In December 1931, he became commander of the Maizuru Naval District and in December 1932 became commander of the IJN 2nd Fleet. In 1933, he commanded the Combined Fleet and the IJN 1st Fleet. Suetsugu promoted rigorous training for the fleet, especially in severe weather conditions. He was promoted to full admiral in 1934, and became commander of the Yokosuka Naval District in December of the same year.