Japan, U.S. to Develop Missile to Intercept Hypersonic Weapons

The Yomiuri Shimbun

Japan and the United States have decided to jointly develop a new type of missile that is capable of intercepting hypersonic weapons being developed by China, Russia and North Korea, The Yomiuri Shimbun has learned.

The two governments will likely reach an agreement at a Japan-U.S. summit meeting slated for Friday, several government officials said.

The two countries will aim to strengthen deterrence by preparing for threats that are difficult to deal with using existing missile defense networks.

This is the second time Tokyo and Washington will jointly develop interceptor missiles since they worked on the SM-3 Block IIA in fiscal 2017.

Arrangements are currently being made for separate bilateral talks in which Prime Minister Fumio Kishida and U.S. President Joe Biden will discuss the joint development and announce it as part of an agreement, on the sidelines of the Japan-U.S.-South Korea summit meeting scheduled for Friday in the suburbs of Washington.

Hypersonic weapons fly at more than five times the speed of sound and travel at low altitudes on irregular trajectories, making them difficult to intercept with existing radar systems.

China succeeded in a launch test of a hypersonic missile in July 2021, and Russia used such missiles in its invasion of Ukraine. North Korea has also repeatedly conducted launch tests of the weapons since September 2021. One analysis suggested that the one Pyongyang tested in January 2022 traveled at a maximum of 10 times the speed of sound.

As a countermeasure, the Defense Ministry is working to improve the capability of the Ground Self-Defense Force’s type 03 medium-range surface-to-air missiles. The new SM-6 missiles planned for the Maritime Self-Defense Force’s Aegis-equipped destroyers also have limited intercept capability. However, none of these missiles can intercept hypersonic weapons until immediately prior to their landing, making it an urgent task for Japan to secure a means of intercepting them at greater distances.

The Japanese and U.S. governments are aiming to develop a new type of interceptor missile within 10 years, according to the sources.

In order to intercept hypersonic weapons, it is also essential to establish a system that can quickly detect and track missiles. The United States is building a constellation of small satellites. The ministry is also looking to work with the U.S. satellite network.

The government is also working toward the possession of counterattack capabilities, which would allow Japan to attack enemy missile launch sites and other locations for the purpose of self-defense.

The government is keen to expedite the joint development of new interceptor missiles, in addition to the development of long-range missiles, to ensure counterattack capabilities. Through these efforts, the government intends to achieve an integrated air and missile defense as soon as possible, which was set forth in the National Defense Strategy last December.