US, Japan Jointly Develop Hypersonic Weapons Interceptor

The United States and Japan last Wednesday signed an agreement to jointly develop a new missile defense system capable of intercepting hypersonic missiles, the next-generation missiles currently being used by both China and Russia and soon North Korea.

The joint project was initially proposed during a summit between President Joe Biden and Prime Minister Fumio Kishida last August. The two leaders reaffirmed the agreement during Kishida’s state visit to Washington last month.

The new defense system called the Glide Phase Interceptor is projected to be ready for deployment within the next decade.

The agreement signed last Wednesday outlines the decision-making process and the allocation of responsibilities, according to officials from Japan’s Defense Ministry.

The Defense Ministry said it hoped to select the Japanese contractors and begin the development process by next March.

Hypersonic missiles can travel at speeds of more than five times the speed of sound, making them difficult for standard missile defense systems to intercept.

The Defense Ministry described the development of interceptors as a “pressing issue” given the dramatic improvement in hypersonic weapons in the region over the last several years.

According to the agreement, Japan would be responsible for developing the rocket motors and the part of the interceptor tip that separates in space before striking the incoming warhead.

Japan’s Defense Ministry said the government will invest 75.7 billion yen (or $490 million US) for the initial development and testing. The cost will include making the components which would then be used by Northrop Grumman and Raytheon Technologies, the US defense contractors developing the interceptors as part of a competition led by the Missile Defense Agency (MDA). The agency will then select one of the two contractors to head up the project.

MDA estimated that developing the hypersonic missile interceptor would cost more than $3 billion, including the investment by Japan.