By Kris Osborn, President, Center for Military Modernization
The People’s Liberation Army is known to have tested ship-deck-launched hypersonic weapons and deployed an air-launched variant from its H-6K bomber, developments which have fueled concerned that the PRC might be inclined to create a “hypersonic” attack bubble or sphere from which to prevent US and allied forces from invading Taiwan.
This kind of contingency has occupied a certain space in the Pentagon’s public discussions about China, as there is concern China might seek to exploit a window of advantage in the realm of hypersonics and essentially establish an “anti-access/area-denial” circle around Taiwan preventing US surface ships, aircraft or land forces from conducting defensive operations within striking range of waters near Taiwan. Should the PRC believe its military has a short-term tactical and operational advantage over the West in the realm of hypersonic weapons, it is conceivable that it could be interpreted as a window of opportunity within which to annex Taiwan.
US – Japan Glide Phase Interceptor Alliance
This threat scenario is likely a key reason the Pentagon is fast-tracking a US-Japan cooperative development agreement to engineer the Glide Phase Interceptor weapon, a next-generation technology designed to track and destroy hypersonics weapons attacks.
“The U.S. Missile Defense Agency is leading the development of GPI for the DoD, which will provide hypersonic missile defense capability during the glide-phase portion of hypersonic flight. Per the signed GPI Cooperative Development (GCD), Japan will lead development of rocket motors and propulsion components of GPI,” a Pentagon statement said.
The GPI is intended to intercept a boost-glide weapon which fires up along the boundary of the earth’s atmosphere before using sheer speed of descent to destroy its intended target. Naturally this kind of defensive weapon incorporates new generations of high-speed tracking technology.
A hypersonic boost-glide weapon, for example, is thrust up into the atmosphere to glide at hypersonic speeds before descending upon its target at unparalleled speed. It is at this “glide” point in the missile’s trajectory where there is the best opportunity to intercept it, just prior to its turning down into its ultimate high-speed descent.
“So when you’re in the glide phase — which is higher up from the terminal, right, where a hypersonic vehicle is likely in its most vulnerable phase — that’s actually a pretty tough environment to be in. And you can’t take an air defense weapon and operate it there nor can you take a space weapon like an SM-3 and operate there, it’s just a different environment,” Navy Vice Adm. Jon Hill, former Director, Missile Defense Agency told reporters, according to a Pentagon transcript from as far back as 2022.
The concept seems clear, as a combined US-Japanese GPI-enabled force could form a semi-circular ring or layer of hypersonic defenses across the Eastern and Southern Pacific around Taiwan. Should the GPII come to fruition as intended, there could certainly be a potential ability to break up, penetrate or simply stop a Chinese hypersonic weapons assault in the Pacific. Earlier thinking from the MDA suggested that the GPI might not be ready until the early 2030s, however it is possible that rapid technological progress is accelerating this timeframe. A joint US-Japanese collaborative effort could speed up this process and offer land-basing opportunities for the weapon.
US Number 3 in Hypersonic Weapons
Indeed senior Pentagon weapons developers have been quite public with comments that the US is currently number 3 in the world in the realm of hypersonic weapons. Russia is of course well known for firing its Tsirkon hypersonic weapon, and China has publicly displayed firings of its ship-launched YJ-21. Perhaps of greatest and most recent concern, a Chinese-government-backed Global Times newspaper published an essay in June of 2023 stating that indeed an air-launched variant of the YJ-21 encircled Taiwan on a H-6K bomber.
“The H-6K bomber is capable of carrying a wide variety of munitions including the KD-20 land attack missile, the YJ-12 supersonic anti-ship missile and the YJ-21 hypersonic missile,” the Global Times reports.
It is quite relevant to point out that the mere existence or ostensible “test-firing” of a hypersonic projectile may not instantly equate to military superiority, as it depends upon the hardening, propulsion, guidance technology and targeting capacity of the weapon, yet Pentagon leaders do often suggest the US needs to “close-the-gap.” Just how sophisticated are China’s hypersonic weapons? For instance, the US is making rapid progress with several promising hypersonic programs to include the land-fired Long-Range Hypersonic Weapon and re-emerging Air Launched Rapid Response Weapon.
Kris Osborn President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.
