At the time of the attack on Pearl Harbor, Hashimoto was in command of the 3rd Destroyer Flotilla, covering landings of Japanese forces in Malaya. From August until late-November, 1942, he commanded Tokyo Express missions during the Guadalcanal Campaign. In January 1943, Hashimoto's destroyers participated in “Operation Ke”, and successfully evacuated 11,700 surviving Japanese troops from Guadalcanal.