Japan has unveiled plans for a new long-range anti-ship cruise missile with interchangeable warheads, the latest development in its effort to deter China’s missile threat at sea.
This month, The Warzone reported that the Japanese Ministry of Defense (MOD) awarded a US$257 million contract to Kawasaki Heavy Industries (KHI) to develop an “island defense anti-ship missile” featuring a stealthy turbofan-powered design with a purported 2,000-kilometer range.
The report mentions that the missile will feature a “modular warhead” with land attack, electronic warfare (EW) and reconnaissance configurations.
It also says the missile will use multiple guidance systems through different stages of flight, such as global positioning system (GPS) and inertial navigating system (INS) during its cruise phase and infrared (IR) or radio frequency (RF) seekers during its terminal phase, increasing kill probability and resistance to countermeasures.
The Warzone notes that the missile will have a length of six to ten meters and fly at high subsonic Mach 0.8 speed.
Asia Times noted in January 2023 that launching multiple types of missiles in one attack can significantly improve accuracy, with a reconnaissance missile having a high-performance camera to spot the enemy’s position, followed by an EW missile to disable enemy radar and other sensors, after which a missile with a high explosive warhead delivers the lethal strike.
The growing missile threat from China and North Korea, alongside the limitations of current missile defenses, may have prompted Japan to invest in long-range pre-emptive strike capabilities, with the missile threat posed by China now evolving with a maritime dimension.
Asia Times noted in May 2022 that China alone has 1,900 ground-launched intermediate-range ballistic missiles (IRBM) and 300 intermediate-range cruise missiles pointed at Japan. North Korea also has hundreds of ballistic missiles that can strike Japan.
Those threats have pushed Tokyo to acquire long-range missiles for pre-emptive strike capability. Attacking the base of a guided missile may fall under Japan’s scope of self-defense if there are no other defensive options.
China now also has hypersonic missile-armed warships. Asia Times reported in October 2022 that China can now deploy hypersonic weapons aboard its carriers and deploys the YJ-21 hypersonic missile aboard its Type 055 cruisers.
Japan’s new anti-ship cruise missile marks a significant step toward taking its pre-emptive defensive posture to sea, with drones possibly acting as target designators.
Asia Times reported in March 2023 that Japan is mulling the use of drones to intercept foreign aircraft intruding into its airspace. This year, Japan will start testing drones to chase warships to gauge performance and functionality. If successful, Japan will next test drones against aircraft.
Those drones may provide the necessary intelligence, surveillance, reconnaissance (ISR) and target acquisition for Japan’s upcoming new anti-ship missile.
Information-sharing between Japan and its allies may also considerably improve the lethality of its upcoming anti-ship missile. As Japan has limited long-range ISR and target acquisition capabilities, such an arrangement can offset that capability gap.
Asia Times reported this month on US plans to link Taiwan and Japan’s MQ-9 Sea Guardian drones with a common system to enable real-time information exchange.
That arrangement would allow the US and its partners to observe the same picture the drones capture, giving all three access to a common operating picture. The US and its partners are taking a practical approach to the program to ensure that integration is done quickly.
Apart from the island defense anti-ship missile, Japan is developing other types of missiles to bolster its deterrent posture against China and North Korea.
Asia Times reported on May 2023 that Japan’s MOD had signed four contracts with Mitsubishi Heavy Industries to design and manufacture various standoff missiles.
These contracts include US$1.29 billion to upgrade Type 12 SSM missile production, US$200 million to develop Type 12 SSM ground/air/ship-launched variants, US$891.8 million for Hyper Velocity Gliding Projectile (HVGP) mass production, and US$436 million for the development of a submarine-launched guided missile.
The upgraded Type 12 SSM will start production this year and is slated to enter service in 2026, with successive upgrades increasing its range to 200, 900 and eventually 1,500 kilometers.
Japan also has two hypersonic weapon designs, with the HVGP Block 1 stated for production this year, with an estimated range of 500 to 900 kilometers, fired from a two-round truck-based launcher.
The other designs, Block 2A and 2B, have ranges of 2,000 to 3,000 kilometers and are slated to be developed from 2023 to 2027 and 2023 to 2030 respectively.
Japan is also planning to develop an extended-range submarine-launched Type 12 SSM between 2023 and 2027 alongside a new class of submarines equipped with vertical launch systems (VLS) to fire larger missiles.
The limitations of Japan’s existing missile defense systems may have prompted it to invest in pre-emptive strike capabilities at sea.
Ship-launched hypersonic missiles such as the YJ-21 can skip along the upper atmosphere for greater range, operate at altitudes too high or too low for traditional missile defenses such as the Aegis and Patriot, and maneuver on unpredictable flight paths to increase the difficulty of interception.
Hence, the best defensive option may be to take out hypersonic-armed ships in a pre-emptive strike before they could launch their missiles.
Japan’s missile splurge may also be due to its vulnerability to a blockade as an island nation, which in a conflict scenario could cut it off from critical imported missile components and stocks.
Deterring or breaking a blockade may require maximum independence from foreign missile suppliers.
While the US is Japan’s primary arms supplier, in a conflict scenario, the US will need all the missiles it can manufacture, potentially leaving few to spare for Japan.
Stockpiled missiles have a limited lifespan measured in years, and for Japan, stockpiling by buying US stocks may be an unsustainable option.
Japan also needs indigenous missile manufacturing capabilities to sustain a high rate of fire over a sustained period should a Taiwan Strait or Korean Peninsula crisis escalate into a war of attrition.