Japan's military, which has spent decades focused solely on self-defense, is making a new kind of weapon to deliver an explosive payload at supersonic speeds. The unconventional tech is designed to soften up enemy defenses with precision strikes before Japanese marines hit the beach, in a bid to help the country take back territory seized by potential adversaries in the future.
The "high speed gliding missile" fills the hole of long range precision attack in Japan's defense capabilities. The weapon consists of two stages: a booster rocket stage, which accelerates it to supersonic speeds, and a second aerodynamic warhead that separates from the booster and glides the rest of the way to the target.
There is nothing like the HSGM in service anywhere. Although several countries field tactical ballistic missiles, including Russia's 9K720 Iskander tactical ballistic missile and South Korea's Hyunmoo 2A ballistic missile, both deliver their warheads using high altitude ballistic trajectories. Japan's missile, on the other hand, probably glides to target at a lower altitude. In fact, HSGM sounds a lot like a boost glide hypersonic weapon system, which flies a similar profile (but at speeds exceeding Mach 5).
Since the end of WWII, Japan's defense-focused military has avoided anything resembling offensive military capabilities. Long-range missiles, bombers, aircraft carriers, and Marines were all classified offensive weapons and therefore off-limits.
Times are changing. New territorial disputes with China-and China's enormous military-have spurred Tokyo to develop certain types of these weapons, including a brigade of amphibious marines, meant to take back Japanese territory captured in wartime.
For most countries, particularly the U.S., precision attack missions in support of ground forces would be handled by Tomahawk cruise missiles or aircraft using weapons such as the Stormbreaker, a bomb that launches from a plane like the F/A-18E/F Super Hornet and glides up to 40 miles to its target. But Japan's Air Self Defense Force is structured to conduct primarily air-to-air warfare. In a war with China, the service would have its hands full fending off superior numbers of Chinese aircraft. The new HSGM weapon gives the Japanese military the capability to strike targets without diverting tactical aircraft from the aerial battle.
Japan is developing two versions of HSGM, a more conventional weapon with low glide capability ready by 2026 as well as a weapon "shaped like a talon with high gliding capacity" by 2028. The weapon is expected to have a range between 217 and 310 miles but Japanese defense officials acknowledge that once the system works greater ranges are attainable.