
Japan steps up defence capabilities in new domains, with eye on China and Russia
- Analysts say Tokyo’s focus on space, cyberspace and the electromagnetic spectrum is purely defensive in the face of evolving security challenges
- It has set up an electronic warfare unit and plans include more satellites, countering hackers, and a plane designed to jam enemy radar
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These changes have accelerated in recent years, as reflected in Japan’s annual defence white papers, and Tokyo is explicitly looking to the rapidly evolving realms of outer space, cyberspace and the electromagnetic spectrum to counter similar moves by China and Russia.
“But it is important to note that these enhancements that are being made to national security are purely defensive and Japan has no intentions of starting an offensive conflict,” he told This Week in Asia.

Under the government’s national defence guidelines – which consistently reiterate that Japan’s security concerns are solely defensive – Japan is committed to launching and using more information-gathering and communications satellites for its own forces, but also develop systems with the “capability to disrupt opponents’ command, control, communications and information” capabilities.
Japan is using the knowledge of the civilian-controlled Japan Aerospace Exploration Agency (JAXA) and is working with the US and “other relevant countries”. The plans also call for the creation of dedicated space security personnel and units.
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The second area of focus is the cyber domain, which has attracted attention in Japan given that North Korea is known to employ thousands of hackers dedicated to compromising other countries’ defence establishments and infrastructure, while others have been tasked by the regime with gaining access to financial institutions and stealing funds.
To counter this, and the threats posed by foreign hackers, Japan is strengthening its command and control systems and networks, including developing methods of damage limitation and recovery. Japan is also developing a reactive offensive capability in this area should the need arise.
It’s completely defensive in nature and designed to help Japan defend its outlying islands, which are Tokyo’s biggest concern
The third element of the revised approach to national security is through “ensuring superiority in the electromagnetic domain”. This includes protecting Japan’s own electronic communications while intercepting and interpreting those of its enemies; conducting electronic jamming; and developing the ability to “neutralise” the radar and communications of “an opponent who intends to invade Japan”.
An 80-member electronic warfare unit was set up in March at a Ground Self-Defence Force base in Kumamoto, in Kyushu, tasked with detecting and analysing airborne communications and radar signatures. Five further units are to be set up around Japan by the end of 2022, with their headquarters at Camp Asaka in Tokyo.
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The Defence Ministry is also developing an electronic warfare aircraft designed to jam enemy radar transmissions, while the Space Operations Squadron will be created by the end of this financial year with an initial complement of 70 personnel.
Elsewhere, a space surveillance radar is being constructed in Yamaguchi Prefecture and is due to come on line in 2023, while the ministry intends to establish a cybersecurity unit of around 540 staff, bringing together experts from the armed forces and private sector.
“These developments involve several thousand people, but it would be hard to describe them as huge,” said Garren Mulloy, a professor of international relations at Japan’s Daito Bunka University and an authority on defence issues.
“This is quite specifically not a power-projection move, it’s completely defensive in nature and designed to help Japan defend its outlying islands, which are Tokyo’s biggest concern,” he said.
“But this is also the direction that warfare is headed,” he added. “Back in the early 1990s, military planners talked about the ‘Three Cs’ of command, control and communications. By the end of that decade, they had added a fourth C, for computers.”
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The “next step up” is known as C4ISR, which brings in intelligence, surveillance and reconnaissance, Mulloy said, as nations seek better information upon which their military forces can act.
Ultimately, this military race has taken nations into outer space, where China and Russia have both demonstrated the ability to knock out enemy satellites with missiles.
“These are small numbers and are not on the same scale as the US or China, but I expect Japan will gradually increase its investment and capabilities in these areas and look to make the most of its home-grown technologies,” Mulloy said.
