Over the past few years, Japan has pushed its military space activity into the spotlight. In early 2020, the nation announced plans for its own military space unit and launched the eighth in a network of reconnaissance satellites. Noting the importance of military activity in space, Prime Minister Shinzo Abe said in late 2019 that Japan’s Air Self-Defense Force may evolve into the Air and Space Self-Defense Force. And its 2018 National Defense Program Guidelines call for the capability “to disrupt opponent’s command, control, communications and information” to ensure superiority in space—the first official document citing the need for counterspace systems.
The recent attention paid to military activity in space along with the country’s suite of developing and developed defense space assets—including its planned deep-space radar that will detect objects in high orbits — suggest Japan is well on its way to becoming a major defense space power. Given its policies up until a little over a decade ago, this level of activity seems remarkable. For almost 40 years, Japan held the position that its space activity was to be nonmilitary, a position that aligned with its post-World War II pacifist constitution. In 1969, it passed a formal resolution excluding military space activity. That position remained intact until 2008, when the country passed the Basic Space Law, which set the parameters and direction for its space policy. Considering its sudden focus on space security, analysts have said Japan is in the midst of a “rapid space militarization.”
As I discuss in a recent paper, this characterization misses the true arc of Japan’s military space activity. Despite the 1969 resolution, Japanese policy decisions have pushed gradually toward space security over the past four decades. These decisions have had the cumulative effect of softening the distinction between nonmilitary and military space capabilities. Rather than in a state of rapid militarization, Japan is actually on an incremental shift toward space security, as reflected in its history and current space policy debates.
A Brief History of Japan’s Space Militarization
Japan’s first foray in military space activity could be traced to the mid-1980s, when its government started buying imagery from U.S. and French satellites for Japan’s defense agency, among other agencies. The government defended its military’s use of satellite imagery as being consistent with the 1969 resolution because the imagery came from civilian satellites.
In 1998, Japan took another important step. The government decided to develop its own reconnaissance systems called Intelligence Gathering Satellites. This marked the first time Japan acquired satellites with a direct military application. This system was not however under the responsibility of the Ministry of Defense. In March 2003, the same month that Japan launched the first Intelligence Gathering Satellite, it established an office to oversee the reconnaissance capability. The government’s decision to keep the satellites out of the defense ministry allowed it to remain consistent with its interpretation of the 1969 position. However, the effect was clear: the lines between military and nonmilitary space capabilities had blurred even further.
In 2008, by the time Japan passed the Basic Space Law, formally changing its position on military space activity, the country already had a four-satellite reconnaissance system and had laid the groundwork for its navigation satellites, another capability with military application. Japan’s passage of the Basic Space Law was clearly important, but it was less an inflection point than a dot on an existing trajectory.
Current Debates in Japan on Space Security
Twelve years later, Japan’s gradual shift toward space security has sparked debates among Japanese space policy experts. Although consequential, these debates are narrow. They center on incremental changes. They do not question whether to expand military space capabilities, just how to go about it.
For example, as Japan has embraced security in space over time, the country has pursued defense space assets that either complement U.S. capabilities — such as its navigation satellites — or are independent of U.S. systems, such as its Intelligence Gathering Satellites. The country is still debating whether it should be developing independent systems, systems that complement U.S. capabilities, or both. Experts told us that these investment decisions do not reflect a serious philosophical divide. Crucially, even when Japan develops independent capabilities, they are designed to be interoperable with U.S. systems. Said Yasuhito Fukushima of the National Institute for Defense Studies in Japan, “Japan’s security space activities are premised on cooperation with the United States.”
As another example, the introduction of counterspace capabilities in its recent defense guidelines has triggered questions about which counterspace systems Japan should pursue, if any. Officials told us that the country is considering moderate jamming capabilities that could be construed as defensive in nature, but the country is not considering more aggressive systems, such as orbital kinetic weapons.
One potential shift in Japan’s counterspace capabilities could be revising Article 9 of its pacifist constitution, which renounces the threat or use of force and war as a sovereign right of the nation. Revising Article 9 reportedly remains a top priority for Prime Minister Abe. Any constitutional amendment requires approval by two-thirds of both houses of the Diet (the Japanese parliament) and a majority in a national referendum. However, even if successful, according to the experts interviewed, this would have little impact on Japan’s counterspace ambitions. One official told us revising Article 9, “won’t drive us to develop counterspace weapons. No one is arguing for that.”
Japan is one of the most mature spacefaring nations in the world. It had the fifth largest space budget in 2018 and had the fourth most satellites in orbit as of 2019. The country is one of five that has its own position, navigation, and timing satellites — the crème de la crème of space capabilities—and one of six, plus the European Space Agency, that can independently launch satellites into higher orbits. As such, its decisions over its defense space policy matter not just for itself but also for the broader space and security environment. The world should take note that Japan’s shift in focus did not begin suddenly, nor will it end precipitously, but it will likely continue, gradually, in the decades to come.
Sam Wilson is a policy analyst at the Center for Space Policy & Strategy at The Aerospace Corporation. He focuses on international space, nuclear command and control, and missile issues.