On April 16, 1945, Corporal Bush, was serving in the 1st Battalion, 4th Marine Regiment, 6th Marine Division as a rifle company squad leader when he led his men in a charge against an enemy stronghold during the final assault against Mount Yaetake in northern Okinawa. During that action, he was seriously wounded and evacuated to a nearby medical aid area for treatment. While at this position, an enemy grenade was hurled among the navy corpsmen and wounded Marines including himself. He immediately took and placed the grenade under himself saving his comrades lives. He survived the blast with severe wounds, losing several fingers and the sight in one eye.