Plaque: Escort Flotilla Four JMSDF (Japan Maritime Self Defense Force, the naval branch of the Japan Self-Defense Forces. The JMSDF has a large fleet and its main tasks are to maintain control of Japan's sea lanes and patrol territorial waters. There are four Escort Forces, each composed of one helicopter destroyer as a command ship, two guided-missile destroyers and 5 standard or ASW destroyers. The Fourth Escort Force is based in Kure, Japan, and occasionally visits San Diego.