Why Japan’s hypersonic and underwater weapon plans might worry China

China has expressed concern over Japan's military advancements, specifically its plans to equip submarine drones with long-range missiles and test hypersonic weapons in Australia. Analysts suggest these developments could pose a threat to China's People's Liberation Army (PLA) forces operating within the strategically vital "first island chain," which extends from Japan to Taiwan and the Philippines. China's defense ministry spokesman stated that Japan's actions, which include expanding its military arsenal, bear a resemblance to pre-World War II militarization. These moves are part of Japan's recent adoption of a "counterstrike capability" under its 2022 security strategy, allowing for strikes on adversary territory for self-defense following an armed attack.

Japan's Defense Ministry has disclosed plans for an 8.9 trillion yen ($55.6 billion) budget request for the upcoming fiscal year, focusing on modernizing its defense capabilities. The strategy involves integrating drones, artificial intelligence, and new warfare methods to enhance deterrence and response capabilities, adapting to evolving global security challenges. Key initiatives include the development and mass production of low-cost uncrewed weapons, such as attack drones and hypersonic missiles, to improve counterstrike effectiveness and address personnel shortages. Japan also aims to bolster its command and control systems with an integrated AI platform and establish a secure "Defense Ministry cloud." To ensure a stable defense industry, the government plans to support companies' research and development and potentially implement a state-owned, contractor-operated system for equipment production.