U.S. Marines with Marine Wing Support Squadron 172 refuel an MV-22B Osprey at a forward arming and refueling point in preparation for exercise Resolute Dragon 21, Dec. 3, 2021 at Ojojihara Proving Grounds, Japan. RD21 is the largest bilateral field training exercise between the U.S. Marine Corps and Japan Self-Defense Force in 2021. RD21 is designed to strengthen the defensive capabilities of the U.S.-Japan Alliance by exercising integrated command and control, targeting, combined arms, and maneuver across multiple domains. - U.S. Marines with Marine Wing Support Squadron 172 refuel an MV-22B Osprey at a forward arming and refueling point in preparation for exercise Resolute Dragon 21, Dec. 3, 2021 at Ojojihara Proving Grounds, Japan. RD21 is the largest bilateral field training exercise between the U.S. Marine Corps and Japan Self-Defense Force in 2021. RD21 is designed to strengthen the defensive capabilities of the U.S.-Japan Alliance by exercising integrated command and control, targeting, combined arms, and maneuver across multiple domains.