Japan Ground Self-Defense Force soldiers fire 120 mm mortar systems on San Clemente Island, Calif., Feb. 13, 2014, during exercise Iron Fist 2014. Iron Fist is a three-week bilateral training event held annually between the U.S. Marine Corps and the Japan Ground Self-Defense Force designed to increase interoperability between the two services while aiding the Japanese in their continued development of amphibious capabilities.