The JS Izumo (DDH-183) is the lead ship of Japan’s new Izumo class of helicopter carriers that are helping cement Tokyo’s role as the dominant blue water naval power in east Asia. The Izumo class represents an ongoing commitment by the Japan Maritime Self-Defense Force (JMSDF) to invest in improving its navy, including offensive capabilities. Japanese forces are adapting to new interpretations of the role Self-Defense forces can play in securing Tokyo’s interests. The Izumo-class carriers will be outfitted with anti-submarine warfare (ASW) helicopters, a nod to the threats posed to Japan and its extended maritime supply routes by the regional navies of Russia, China and to a lesser extent North Korea. Though the Japanese do not (yet) plan to develop fixed-wing carrier capabilities vis-à-vis the U.S. Navy, they remain ably equipped to handle potential threats to their maritime sphere of influence, principally by China. The lynchpin of the People’s Liberation Army Navy rests on its submarine fleet, resulting in Japan’s investment and training in ASW and development of its own advanced submarine fleet as well. As the United States reduces its overall naval presence in the Pacific, the JMSDF will increasingly move into spaces vacated by Washington to the consternation of the Chinese and the Koreans, but potentially to the delight of weaker states such as the Philippines.