NATO's Evolving Space Security
- Implications for Japan's Space Strategy

Introduction

As a political and military alliance, the North Atlantic Treaty Organization (NATO) has been forced to adapt to changing circumstances and emerging threat risks. It has continued to transform itself across every field, from organizational structure to operational management.[1] Since the mid-2010s, addressing threats in the cyber domain has become a strategic challenge, and in the face of present-day vulnerabilities such as accelerated reliance on space infrastructure through digitalization, NATO has continued to systematically work on building deterrence and defense postures in outer space. In recent NATO summits, attention has focused on issues such as the defense burden sharing among member countries and friction between the US and Europe over the ownership of Greenland. As a result, progress in the space sector has often been overshadowed. Given the evolving security environment, however, concrete and future-oriented measures from a space security perspective, such as the establishment of the NATO Space Centre in 2020, will be key to the alliance's strategy.

Why does NATO consider space domain to be so essential for the deterrence and defense of its alliance, and why is it focusing so much on its evolution? To what extent is this movement tangible, and what does it mean for Japan, which underpins its security on the Japan-U.S. alliance? Based on these concerns, this article provides an overview of NATO's space initiatives and argues for the necessity of cooperation between Japan and NATO.

A Quiet Approach to Space

NATO's space-related policies have been established through a steady accumulation of decisions within the North Atlantic Council (NAC). This process began at the London Summit in December 2019, where NATO officially designated space as its fifth "operational domain" for the first time.

Following this designation, further developments followed. In just over two years, NATO solidified its institutional foundation in both defense and deterrence. At the Brussels Summit in June 2021, NATO leaders affirmed that attacks on member assets in space could trigger the collective defense clause (Article 5). At the same time, in order to functionally complement the NATO Space Centre, which coordinates space operations, leaders put forth a development plan for "3SAS" (Strategic Space Situational Awareness System) that will be responsible for Space Situational Awareness (SSA).

In January 2022, this progress was systematized into the first comprehensive overarching "Space Policy." Through this policy, NATO legally and politically positioned space as an essential domain for the conduct of alliance operations.[2]

These developments reflect the reality that outer space is becoming a warfighting domain, and that there is a growing awareness of Russia and China's improved anti-space attack capabilities.[3] According to the U.S. Space Force's space threat assessment, this threat is becoming concrete. Since 2017, Russia has deployed multiple co-orbiting anti-satellite weapons (ASAT) demonstrators in the same orbit as U.S. military satellites. In addition, they are also developing nuclear-powered ASAT that can indiscriminately neutralize low-Earth orbit satellites.[4] China is also strengthening its close-range jamming capabilities in geostationary orbit.

The urgent need to address this reality was inadvertently highlighted by the US conflict with Iran in the first half of 2026. It was striking when General Dan Caine, Chairman of the Joint Chiefs of Staff, first neutralized Iran's communications and sensor networks through coordinated space and cyber operations at the start of the joint operation, reaffirming the critical nature of space operations.[5]

Modern armed conflicts begin in outer space and cyberspace. This proposition – no longer merely theoretical doctrine but backed by real-world combat – demonstrates that NATO's approach to space since 2019 has been the right one.

Governance Challenges and Deepening Reliance on Space

NATO's space efforts are accelerating due to political will based on military assessments. Additionally, the evolution of Emerging and Disruptive Technologies (EDTs)[6] related to satellite miniaturization and AI applications, as well as the rapid expansion of the commercial space sector with its intensive resource investment, are also greatly expanding the alliance's space-related options.

The global space economy is projected to reach $613 billion in 2024, with the commercial sector accounting for 78% of that.[7] Furthermore, according to analyses by the World Economic Forum (WEF) and McKinsey, this market is projected to reach $1.8 trillion by 2035.[8] Following this trend, NATO approved its first "Commercial Space Strategy" at its Defense Ministers' Meeting in February 2025. Announced at the Hague Summit in June later that year, the strategy clearly outlines a commitment to incorporating privately-led innovation and promoting full-scale collaboration with private space companies. The U.S. Department of Defense has already announced a similar Commercial Space Integration Strategy in 2024, and both of them are moving in alignment with each other.

However, these benefits come with undeniable challenges. Communications, positioning, financial settlements, logistics, and agriculture – the foundational functions of modern society – are rapidly becoming dependent on space systems. While this increased reliance on commercial vendors enhances development efficiency, it also introduces new risks.
Governing the increasing complexity of supply chain management, ensuring data confidentiality, and determining responsibility for protecting commercial assets in times of crisis are challenges that have not been adequately considered within the alliance until now.

This change represents a paradigm shift in space security: from possessing proprietary technology to integration with the commercial sector and subsequent risk management. Without this transition, modern space strategy cannot function.

The Connectivity Japan should Build with NATO

At the Defense Industry Forum held in conjunction with the Ankara NATO Summit in July 2026, a new direction for NATO's space strategy was outlined.[9] The strategy included HALO (Hybrid Alliance Layered Operations in Space), which focuses on high-speed communication and missile tracking, and APSS (Alliance Persistent Surveillance from Space), which aims to enhance Intelligence, Surveillance, and Reconnaissance (ISR) capabilities.

HALO, a new project started by eight countries, aims to interconnect military satellites under each country's sovereignty, effectively creating a mega-constellation (a large group of satellites). While discussions are accelerating due to expectations of public-private partnerships, implementation challenges such as funding remain.[10] In contrast, APSS is already in the implementation phase. Nineteen countries contributed a total of $1 billion, and it reached initial operational capability in December 2025. It is the largest space investment in NATO history.[11]

The parallel development of HALO, a symbolic initiative with political impact, and APSS, a foundational project that is steadily being implemented, demonstrate that the alliance is simultaneously advancing both future visions and current implementations in the space domain.

Through these efforts, NATO is qualitatively transforming from a traditional military alliance into a community responsible for sharing space systems and joint defense. Japan should not view this as a transformation outside of their own context. While Japan is strengthening its own space defense capabilities and cooperating in space within the Japan-U.S. alliance, the framework for multilateral cooperation is still insufficient for Japan.

NATO's example could offer clues to solving the challenges of multilateral space cooperation. In fact, Japan and NATO included space security in their 2023 Individually Tailored Partnership Programmes (ITPP)[12]. When it is renewed in 2026, it should be elevated to a priority area with a focus on strengthening security cooperation among Japan, the United States, and Europe.

One motivation for this is the recent evidence of space cooperation. In May 2026, the National Institute of Information and Communications Technology (NICT) and the University of Luxembourg signed a Memorandum of Understanding in the field of information and communications technology, which include low orbit satellite constellations. Since then,, reports have surfaced of Japan being approached about participating in STARLIFT.[13] STARLIFT, which includes 14 allied nations including Luxembourg, is a space-based mutual support system that allows member nations to share launch capabilities and spaceports in times of crisis, enabling the rapid restoration of a malfunctioning satellite network. If Japan, which has the Tanegashima Space Center and the H3 rocket, participates, it is expected to not only secure backup for its own satellites but also contribute to the economy of the regions where the launch sites are located.

Japan and the United States already have a track record of cooperation in Space Domain Awareness (SDA) through the QZSS (Quasi-Zenith Satellite System Hosted Payload) program, which was completed in August 2026.[14] These developments are clear. Moving forward, Japan is expected to play a leading role in strengthening connectivity and interoperability in the space domain with NATO, while building upon the foundation of the Japan-U.S. alliance.

Conclusion

The focus of space security is shifting from the advanced technological capabilities of individual nations to combining commercial use with international partnerships. NATO's efforts in space are the result of steadily strengthening its internal alliance structure, leveraging growing threat awareness and the dynamics of innovation shifting from state-sponsored to civilian-led initiatives.

For Japan, which bases its security on the Japan-U.S. alliance, NATO is no longer merely a distant European alliance structure. What is important for Japan is to deepen existing cooperation frameworks and improve space cooperation with NATO, including establishing an international mechanism for sharing space technology and data. Building upon the space security cooperation that has been cultivated between Japan and the United States, promoting similar cooperation between Japan and NATO will be an essential strategic challenge for strengthening Japan's defense capabilities.

(2026/09/30)