Japan shoring up missile defenses to deter North Korea
Japan is pushing to upgrade its missile defenses and more closely coordinate with South Korea and the United States to guard against possible North Korean missile strikes.
Japan’s current missile-defense system uses land-based Patriot missile batteries, pictured, and sea-based SM-3 interceptor missiles launched from destroyers. Both can shoot down incoming ballistic missiles, said Jeffery Hornung, a Japan specialist with the Rand Corp.
“The system itself is limited capability-wise,” Hornung said. If North Korea launches a missile toward a city that’s not one of Japan’s largest, “chances are there’s no Patriot system up ready to go protecting anything that’s not Tokyo, Osaka or major bases in Japan.”
The land-based Aegis Ashore missile defense system, which Japan plans to install, could fill in these gaps, Hornung said. It would offer longer-range protection and would cover more territory. “Theoretically, it would be able to cover Chinese missile threats as well,” Hornung said of Aegis Ashore, which is slated to be operational by 2023. Japan is currently evaluating sites for the system’s deployment.
Communication and information-sharing with South Korea and the U.S. must also run smoothly to ensure adequate missile defense, Hornung added. Japan’s constitution limits what military actions it can take in its own defense, so many considerations must be taken into account before Japan shoots down a missile.
“They have to determine if there’s no other means to take care of the threat,” Hornung said, “and they have to determine if it is a threat to Japan’s survival. All these political decisions have to be made really, really fast because the time it takes for a missile to reach them from the Korean Peninsula to Japan is just 17 minutes.”
Such decisions are made easier by the General Security of Military Information Agreement signed in 2016 by Japan and South Korea. Hornung said the agreement eliminates the need to use the U.S. as a bridge between the two countries when it comes to intelligence-sharing, thereby saving valuable time. Seoul’s surveillance of Pyongyang’s communications, for example, could be shared with Tokyo, and imagery gathered by Japan’s powerful satellites could be shared with Seoul.
Deterring North Korean missile attacks from ever being launched is helped by the fact that Japan and South Korea host U.S. military assets.
“You have the Air Force down in Kadena, and in Yokosuka, the 7th Fleet, in addition to the bombers that would be flying out of Guam,” Hornung said. “You have the Marines and the Air Force in massive numbers in Okinawa and a huge Army presence in Korea. The North Korean military is really looking down the barrel of the full force of the United States Armed Forces. All four services, so that should provide some level of deterrence.”
Tom Abke is a FORUM contributor reporting from Singapore.