TOKYO -- Japan is considering upgrading to a next-generation missile interceptor that could reach higher altitudes than existing models, as well as adding a third layer to its missile defense scheme, in response to North Korea's rocket launch Sunday.
Japan and the U.S. are developing the Standard Missile-3 Block IIA system, which can be loaded on Aegis-equipped destroyers. The new interceptors will be tested for accuracy for the first time this fall off Hawaii. The aim is to begin production in fiscal 2017 and deployment by fiscal 2019.
Existing SM-3 interceptors can hit targets only about 300km above ground. The new system will be able to reach an altitude of over 1,000km. "The higher we intercept the missiles, the more area we can defend," a Japanese Defense Ministry official said.
Each destroyer equipped with the Block IIA will be able to defend a radius of about 1,000km, significantly more than the current range of several hundred kilometers. Japan needs three Aegis destroyers equipped with the existing interceptors to protect its territory, but "two will be enough if we have the new SM-3s," the official said.
Tokyo also is looking at installing the land-based Terminal High Altitude Area Defense system, or Thaad. "There are no plans for the Self-Defense Forces to deploy Thaad," Chief Cabinet Secretary Yoshihide Suga told reporters Monday. But he also said that to protect Japan, the government will "study U.S. military equipment and speed up deliberations on adopting them."
Thaad is used against missiles that have re-entered Earth's atmosphere, and it can reach targets with an altitude of up to about 150km. It would serve as the intermediate defense between SM-3s and Patriot Advanced Capability-3 missiles. The PAC-3 system is deployed by the Air Self-Defense Force and can hit missiles up to about 20km above ground.
But the Defense Ministry is cautious about Thaad. "It is extremely expensive to install," a ministry official said.
China has protested moves to deploy Thaad at U.S. military bases in South Korea, likely concerned that American radar will gain information about Chinese missile bases in the country's interior regions. Japan could trigger Chinese objections depending on whether and where it decides to deploy Thaad.