Japan’s Urgent Space Defense Revolution: How Commercial Technology is Shaping the Future of National Security

On December 4, 2024, the US Space Force launched a new unit at Yokota Air Base in Tokyo. This unit, called US Space Forces Japan, aims to bolster the US military’s operations in space. In a meeting the month before, US and Japanese defense ministers hailed this as a key step in improving space defense cooperation, a field seeing rapid advancements.

At the same time, Japan’s Air Self-Defense Force opened a Space Cooperation and Innovation Office in central Tokyo in 2023. This office is focused on collaborating with private companies to tap into civilian aerospace technology for military application. This move aligns with the growing view, shared by both Japan and the US, that leveraging civilian technology is crucial for space defense progress. Let’s explore some innovative efforts from both nations and the hurdles Japan faces ahead.

US Defense Innovation Efforts

In the mid-2010s, the US Department of Defense (DoD) introduced various initiatives aimed at keeping its military tech ahead, especially against threats from China. This led to the creation of the Defense Innovation Unit (DIU) and other entities working to speed up the use of commercial technologies in defense.

While some of these units, such as DIU and AFWERX, have shown success in developing advanced technologies, concerns have been raised about their overall impact on military readiness. Critiques suggest that these innovation units often struggle to transition promising prototypes into actual military procurement processes, which diminishes their effectiveness.

Creating a New Space Framework

The US Space Development Agency (SDA), founded in 2019, is reshaping the military’s approach to space acquisition. Unlike the existing large satellites, which are costly and vulnerable, the SDA emphasizes a network of small, affordable satellites designed for resilience and rapid updates.

Known as “proliferated architecture,” this approach means using numerous satellites that can withstand attacks. The SDA also follows a “spiral development” model, launching new satellite batches every two years for continuous upgrades. The first demonstration satellites launched in 2023, and more are set to follow soon.

Representation of the US Space Development Agency’s Space Architecture (Source: Space Development Agency.)

The SDA is operating under the US Space Force but retains significant independence. Its budget has seen consistent increases, with Congress recognizing its potential. In fact, the US Space Force is shifting priorities based on the SDA’s success, even cutting back on more traditional satellite projects.

Japan’s Emerging Space Defense Program

Japan’s current military space capabilities are limited to three operational communication satellites. Until recently, strict constitutional rules held back the use of space for defense purposes. However, the Basic Space Law enacted in 2008 opened the door for Japan to develop a more robust space defense strategy.

The Japanese Defense Ministry is already moving forward with plans to develop small satellite constellations similar to the US approach. They’ve tested communication satellites like SpaceX’s Starlink to improve military communications. Furthermore, Japan’s fiscal 2025 budget proposes a new satellite system for tracking military targets, with potential construction starting in March 2026.

This project stands out for its intention to leverage existing commercial technologies while fostering a local space development ecosystem that includes innovative startups.

Integration Challenges Ahead

While Japan’s Defense Ministry is making strides, integrating space systems with ground operations presents significant challenges. The proposed constellation for long-range target tracking is vital for Japan’s broader defense strategy, which aims for capabilities beyond its borders as outlined in its 2022 National Security Strategy.

A visualization of Japanese plans for a standoff defense capability, published in the Defense Ministry’s white paper, Defense of Japan 2024.

Addressing these integration issues will be key for Japan’s military as they continue to develop their space capabilities. While they have started to explore these technological avenues, there is still much to learn from the ongoing developments in the field.

In October 2024, Japan’s Acquisition, Technology, and Logistics Agency set up the Defense Innovation Science and Technology Institute in Tokyo. This institute aims to push for innovative military applications while also advancing rapid technological development.

The efforts of the US and Japan to enhance their space defense capabilities by leveraging commercial technologies could greatly impact their military effectiveness. For Japan, the vital challenge will be integrating these systems effectively, a hurdle they must overcome to address the security demands of the modern world.

(Originally published in Japanese. Photo: A demonstration of a satellite-based situation monitoring exercise by the Air Self-Defense Force in Tokyo, November 30, 2021. © Jiji.)