Marines and sailors with 2nd Battalion, 3rd Marine Regiment and members of the Japan Ground Self-Defense Force, 30th Infantry Regiment, 12th Brigade, Eastern Army practice casualty evacuation drills during Forest Light 17-1 at Camp Soumagahara, Mar. 9, 2017. Forest Light is a routine, semi-annual exercise conducted by U.S. and JGSDF in order to strengthen interoperability and combined capabilities in defense of the U.S.-Japan alliance. - Marines and sailors with 2nd Battalion, 3rd Marine Regiment and members of the Japan Ground Self-Defense Force, 30th Infantry Regiment, 12th Brigade, Eastern Army practice casualty evacuation drills during Forest Light 17-1 at Camp Soumagahara, Mar. 9, 2017. Forest Light is a routine, semi-annual exercise conducted by U.S. and JGSDF in order to strengthen interoperability and combined capabilities in defense of the U.S.-Japan alliance.