Japan, US move ahead in co-developing hypersonic weapons interceptor as regional threats grow
TOKYO — Japan and the United States signed an agreement on Wednesday to jointly develop a new type of missile defense system as the allies look to defend against the growing threat of hypersonic weapons owned by China and Russia and being tested by North Korea .
The project was initially agreed between Japanese Prime Minister Fumio Kishida and US President Joe Biden during their summit in Washington last August. The Glide Sphere Interceptor is expected to be deployed in the mid-2030s.
Wednesday’s agreement determines the division of responsibility and the decision-making process, a first major step in the project, Japanese Defense Ministry officials said. They hope to make a decision on Japanese contractors and start the development process by March 2025.
Hypersonic weapons are designed to exceed Mach 5, or five times the speed of sound, and pose a threat to regional missile defense systems with their speed and maneuverability. Developing its interceptors is a challenge.
Japan’s Defense Ministry called it an “urgent issue” and noted that hypersonic weapons have improved dramatically in the region in recent years.
Under the arrangement, Japan is responsible for developing a component at the tip of the interceptor that separates in space to destroy the incoming warhead and its rocket motors, officials said.
Japan has set aside 75.7 billion yen ($490 million) for the initial development and testing of the interceptor, according to the Defense Ministry.
The costs include making components for the two companies, Raytheon Technologies and Northrop Grumman, that are developing the weapon in a competition led by the U.S. Missile Defense Agency. One will be chosen for the project.
The MDA estimates that the cost of developing the hypersonic missile interceptor will exceed $3 billion, including Japan’s share of $1 billion.
The interceptors will be deployed on Aegis-class destroyers, such as the ship-to-air Standard Missile-3 that Japan previously developed together with the United States.
Japan has accelerated its military build-up as it emphasizes the need to strengthen its deterrence against growing threats. Japan has also significantly relaxed its arms export policy to allow co-developed lethal weapons to third countries.