Japan, US move forward in joint development of hypersonic weapons interceptors as regional threats rise

TOKYO (AP) — Japan and the United States signed an agreement Wednesday to jointly develop a new type of missile defense system as the allies seek to defend against the growing threat of hypersonic weapons, which the countries possess. 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 at their summit last August and reaffirmed between the leaders during Kishida’s visit to Washington in April. The Glide Sphere Interceptor is expected to be deployed by the mid-2030s.

Wednesday’s agreement determines the distribution of responsibilities and the decision-making process, a major first step in the project, Japanese Defense Ministry officials said. They hope to choose Japanese entrepreneurs and start the development process by March 2025.

Hypersonic weapons are designed to exceed Mach 5, or five times the speed of sound, posing a threat to regional missile defense systems due to their speed and maneuverability. Developing interceptors is a challenge.

Japan’s Defense Ministry called the issue an “urgent matter” and noted that hypersonic weapons in the region have improved significantly in recent years.

Under the deal, Japan is tasked with developing a piece at the interceptor’s tip that separates in space to destroy the incoming warhead, as well as its rocket engines, officials said.

Japan earmarked 75.7 billion yen ($490 million) for initial development and testing of the interceptor, according to the Defense Ministry.

The cost includes manufacturing components for the two companies, Raytheon Technologies and Northrop Grumman, which are developing the weapon in a competition led by the U.S. Missile Defense Agency. One will be chosen for the project.

The MDA estimated that the development cost of the hypersonic missile interceptor would exceed $3 billion, including Japan’s share of $1 billion.

The interceptors will be deployed on Aegis-class destroyers, such as the Standard Missile-3 ship-to-air missile that Japan previously co-developed with the United States.

Japan accelerates its military development because it underlines the need to strengthen its deterrence in the face of growing threats. Japan has also significantly relaxed its arms export policy to allow joint development of lethal weapons to third countries.


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