Japan is seeking a new class of hypersonic guided missiles (HGM) that could be launched from platforms operating beneath the sea, according to plans outlined by the country’s Ministry of Defense. The proposal was included in a budget request document and could represent a significant step toward expanding Tokyo’s sea-based long-range strike capabilities. Although the ministry has not released technical specifications for the proposed weapon, the system is expected to draw on technologies associated with Japan’s Type 25 Hyper Velocity Gliding Projectile (25HGP). The 25HGP is the country’s latest domestically developed weapon intended to support the defense of remote islands while also providing an extended stand-off deterrence capability. A submarine-launched hypersonic system would potentially provide Japan with another method of delivering long-range effects while operating from a concealed maritime position. The proposal therefore indicates Tokyo’s interest in developing strike systems capable of operating from beneath the surface and contributing to the country’s broader defense requirements.
