The announcements triggered media attention and concerns in some overseas capitals, but Japan’s outer space ambitions are not new. Neither do the announcements imply that the country is about to enter the space race heating up between the United States, China and Russia. Japan is still legally restricted when it comes to space activities and capabilities.

Based on Article 9 of the Japanese Constitution, a 1969 parliamentary resolution states that Japanese use of outer space should be only for ‘peaceful purposes’. This meant that space activities could be conducted only by the civilian sector and for the development of civilian technologies.

In 1998, after North Korea launched its Taepodong-1 missile over Japanese airspace, Japan started an Information-Gathering Satellite (IGS) program to monitor Pyongyang. The Japanese government denied violating the 1969 resolution, asserting that multifunction IGSs were dedicated to supporting the exclusively defensive duties of the SDF. The term ‘peaceful purposes’ gradually reinterpreted from its original meaning of ‘non-military’ to ‘non-offensive’.

In the mid-2000s — as the Six-Party Talks on North Korean nuclear weapons between the United States, Japan, South Korea, North Korea, China and Russia stalled — the Japanese government sought a legal revision. In 2008, the parliament approved a new law that permitted space activities ‘to increase the national security of Japan’. This opened the door to the development of early warning and military-grade intelligence satellites. But the use of space is still only permitted today, through non-offensive means.

Japan currently possesses five radar IGSs, two optical IGSs and plans to develop a constellation of eight satellites of both types plus two relay satellites. Tokyo has also begun deploying military communications satellites. In 2017, Kirameki-2 was put into orbit over the Indian Ocean, Kirameki-1 was launched over the Pacific Ocean in 2018 and Kirameki-3 — with a planned orbit over Japan — will be launched this year. Japan is developing its own Global Positioning System (GPS), the Quasi-Zenith Satellite System (QZSS). Four Michibiki satellites are now in orbit and another three are scheduled to be launched by fiscal year 2023.

The objective of Japan’s space strategy is to ensure it maintains in all circumstances the ability to use space-based assets for the combined operations of the SDF. This will tackle the threat posed by anti-satellite (ASATs) weapons and space debris. According to a 2019 report by the Japanese Ministry of Defense, the main dangers are Chinese and Russian ASATs, including ground- and aircraft-launched ballistic missiles, ‘killer satellites’, laser weapons and jammers.

Defending satellites is the primary mission of Japan’s new space unit. The National Defense Program Guidelines released in December 2018 suggest its role is to conduct ‘persistent monitoring of situations in space, and to ensure superiority in use of space at all stages from peacetime to armed contingencies’. The Space Domain Mission Unit, to be based at Fuchu Air Base near Tokyo and initially staffed with about 20 personnel, will become fully operational in 2022. It will cooperate with the US Space Command established by US President Donald Trump last year.

Protecting Japanese satellites requires an in-depth monitoring of space, thus Space Situational Awareness (SSA) space-based optical telescopes and ground-based laser ranging devices will also be deployed. Japan’s SSA capabilities are expected to be connected to US forces in two years. Another dimension of US–Japan cooperation is related to QZSS, as the system is compatible with the US GPS and explicitly dedicated to complementing it in the Asia Pacific.

Japan’s space strategy is almost purely defensive in the sense that it aims to protect against the elimination of space-based assets, which would blind and paralyse the SDF and leave the country vulnerable. Due to legal, political and budget constraints, Japan is not militarising outer space beyond what is necessary to guarantee the proper functioning of the SDF. In other words, Japan is not on the verge of playing a remake of Star Wars.

But this does not mean that Japan’s space program has no offensive dimension. First, one of its stated goals is to build ‘the capability to disrupt C4I (command, control, communication, computer, and intelligence) of opponents in collaboration with the electromagnetic domain’. The future development of Japan’s own ASATs cannot be ruled out. This would certainly trigger domestic debates over their constitutionality as ASATs could arguably violate the non-offensive principle.

Second, Japan’s space-based information gathering and positioning capabilities are key to allowing the SDF to strike targets with precision, for example using the Joint Strike Missile or Joint Air-to-Surface Standoff Missile. It is no secret that some in Japan are seeking the capacity to destroy North Korean missile launch pads and vehicles. And to strike, one must first see.

Lionel Fatton is Assistant Professor of International Relations at Webster University, Geneva. He is also a Research Collaborator at the Research Institute for the History of Global Arms Transfer, Meiji University, Tokyo, and an Adjunct Fellow at the Charhar Institute, Beijing. He is co-author with Oreste Foppiani of the Japan’s Awakening: Moving Toward an Autonomous Security Policy (Peter Lang AG, 2019).