This article is written by Chukwukere Oluomachukwu Mary, Babcock University, an intern under Legal Vidhiya.
ABSTRACT
The growing involvement of states in military activities beyond Earth’s atmosphere has sparked global concern regarding the adequacy of international legal frameworks. While the Outer Space Treaty of 1967 sets foundational norms for peaceful use, loopholes and ambiguities continue to permit military exploitation. This article examines how international space law, especially the Outer Space Treaty, regulates military operations, highlights key limitations, and calls for legal reform in the face of emerging space-based military technologies. Through the lens of treaties, UN resolutions, and customary international law, the paper advocates for clearer, enforceable standards to ensure that space remains a peaceful and cooperative domain.
KEYWORDS
Military, Military in Space, Space Exploration, Space Law, Outer Space Treaty, Liability Convention, Legislation.
INTRODUCTION
Military engagement in outer space is no longer theoretical. With increasing dependence on satellite technologies for defense, surveillance, and strategic superiority, states have begun asserting military capabilities beyond Earth. Against this backdrop, international space law aims to ensure that outer space is used for peaceful purposes, but its ability to constrain military conduct is under increasing strain. Space law addresses military space operations primarily through the Outer Space Treaty of 1967, which prohibits the placement of nuclear weapons or other weapons of mass destruction in orbit, on celestial bodies, or in any other manner in outer space. It also emphasizes that outer space should be used for peaceful purposes, though “peaceful purposes” is open to interpretation, as space technology can be used for both civil and military applications. The ban on the use of force and the applicability of international humanitarian law are also important elements of space law pertaining to military activities. The national space activities of a State include military activities in space and all such ‘national space’ activities are bound to conform to the applicable domestic and international law.
THE OUTER SPACE TREATY AND PEACEFUL USE
The Outer Space Treaty (OST), officially titled the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies (1967), serves as the foundation of international space law. The treaty emphasizes that the exploration and use of outer space for peaceful purposes is a shared interest of all humankind. The UN Legal Subcommittee in 1966 examined the treaty and later approved it through the General Assembly through Resolution 2222 (XXI). It was opened for signature in January 1967 by the United States, the United Kingdom, and the Soviet Union, and officially entered into force in October of that year. To this day, it continues to provide the legal foundation for regulating conduct in outer space.
The fourth article of the treaty (Article IV) prohibits the placement of nuclear weapons or other weapons of mass destruction in Earth’s orbit, on celestial bodies, or at any location in outer space. It also forbids the establishment of military bases, the testing of weapons, and conducting military exercises on celestial bodies.[1] However, it does allow for the presence of military personnel and equipment if they are used for scientific or other peaceful activities, though what qualifies as “peaceful” is not clearly defined.
This lack of definition has led to varied interpretations. Some states understand “peaceful purposes” to mean non-aggressive use, while others see it as a complete ban on military involvement. Despite these restrictions, the OST does not outlaw all military activity in space. It permits conventional weapons to be placed in orbit, as long as they are not WMDs, and does not forbid nuclear-armed missiles that travel through space. A historic example of military activity in space was the Soviet Union’s 1974 launch of the Almaz OPS-2 military station, which carried a 23 mm automatic cannon—the only known instance of a gun being fired in outer space.[2]
MILITARY STRATEGIES AND TECHNOLOGICAL DUAL-USE
Countries like the United States, China, Russia, India, and France have all developed or announced dedicated military space commands. Satellite systems now support battlefield navigation, missile guidance, communications security, surveillance and reconnaissance. Many of these technologies have dual-use potential—serving both civilian and military goals, complicating the task of legal classification. For example, in 2007, China tested an ASAT weapon, and India followed suit in 2019, both generating concerns about orbital safety.[3]
BROADER LEGAL FRAMEWORKS
UN Charter
The United Nations Charter defines the conditions under which states are permitted to use force legally. As a general rule, it prohibits both the threat and use of force, except in two key situations: when authorized by the UN Security Council under Chapter VII, and when a state exercises its inherent right to self-defense, as outlined in Article 51. Article 2(4) forbids the threat or use of force, while Article 51 permits self-defense in response to an armed attack.[4]
The Moon Agreement
The Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, also referred to as the Moon Agreement or Moon Treaty, was adopted by the United Nations General Assembly in December 1979 through Resolution 34/68. After Austria met the criteria for ratification by being the fifth country to ratify the treaty, it came into effect on July 11, 1984. The Moon Agreement was established to elaborate on the provisions of the Outer Space Treaty (OST), especially regarding the utilization and extraction of resources beyond Earth. Expanding upon the OST’s core principles, the Moon Agreement bans any form of ownership or appropriation of lunar or celestial resources by states, entities, or individuals. This provision could be therefore interpreted as limiting the ability of the military to claim, control, or exploit space-based resources for strategic or defense purposes. However, despite its far-reaching intent, the Moon Agreement holds little legal force because major spacefaring nations—including the United States, Russia, and China—have not ratified it. This lack of widespread acceptance significantly undermines its practical impact on future interplanetary missions.[5]
International humanitarian law
International humanitarian law (IHL) establishes rules on the conduct of hostilities with the aim of limiting, for humanitarian reasons, the effects of armed conflict. It includes in particular the principle of distinction, the prohibition of indiscriminate and disproportionate attacks, and the obligation to take all feasible precautions to avoid, or at least to minimize, incidental civilian harm.
In the ICRC’s view, these rules apply not only to kinetic (physical) operations against space objects, but also to non-kinetic operations that would disable space objects without necessarily damaging them physically, such as cyber warfare.
When assessing the lawfulness of such attacks, all foreseeable direct and indirect incidental harm or damage to civilian objects must be considered, including when targeting a space object used for both military and civilian purposes. The risk of creating debris, and its indirect effects, should also be considered when applying these rules. IHL also generally prohibits weapons that cause superfluous injury or unnecessary suffering and are indiscriminate by nature, as well as a number of specific types of weapon.
Law of neutrality
The law of neutrality regulates relations between belligerent states and neutral states in wartime. Like IHL, it also serves to mitigate and contain the adverse effects of an armed conflict. The fact that international law, including IHL, constrains wartime military operations in, or in relation to, outer space neither encourages the weaponization of outer space nor legitimizes hostilities in outer space.
Given the risk of significant harm to civilians, states should consider the potential humanitarian consequences when making any decision, at national and multilateral levels, on military operations in relation to outer space. States may decide to set general prohibitions or specific limits with regard to weapons, hostilities or other military operations in relation to outer space. They may do so for a range of reasons, including humanitarian ones, as they did in the Outer Space Treaty. If new legally binding instruments or other norms, rules and principles are to be developed, they must be consistent with and should build on and strengthen the existing legal framework, including IHL.[6]
Several UN General Assembly Resolutions, such as those under the PAROS initiative (Prevention of an Arms Race in Outer Space), express political consensus but lack binding force. Customary international law is evolving as states increasingly engage in regular space activity and adopt new practices, but consistency remains a challenge.
GAPS AND LEGAL AMBIGUITIES
Although the Outer Space Treaty (OST) of 1967 and its related instruments have laid a foundational framework for the peaceful use of outer space, significant legal gaps and ambiguities continue to undermine their effectiveness, particularly with regard to military activities. These loopholes raise serious concerns about the long-term sustainability, safety, and security of outer space.
While Article IV of the OST explicitly prohibits the placement of nuclear weapons or other weapons of mass destruction (WMD) in orbit, on celestial bodies, or in outer space in general, it is silent on the use or deployment of conventional weapons. This silence creates a dangerous legal void. States could, in theory, deploy non-nuclear weapon systems in orbit or utilize space-based platforms to enhance terrestrial military operations without breaching the treaty. As technology evolves, this silence grows more consequential, enabling new forms of space-based militarization without clear legal constraints.
The OST also fails to address anti-satellite (ASAT) weaponry, which refers to weapons designed to disable or destroy satellites. Although ASAT tests have been conducted by major spacefaring nations such as the United States, Russia, China, and India, there is no treaty-based prohibition against them. These tests often produce orbital debris that threatens the safety of all space actors, both civilian and military. The absence of binding norms or a dedicated ASAT treaty contributes to a dangerous precedent, whereby states may engage in destructive tests with impunity.
Another fundamental weakness lies in the lack of enforcement provisions within the OST and related instruments. There is no international space tribunal or monitoring body with the mandate to investigate violations, enforce treaty compliance, or impose sanctions. Disputes are left to be resolved through diplomatic channels or by state consent, which is often impractical during armed conflict or geopolitical tensions. This absence of compulsory dispute resolution mechanisms and accountability measures significantly weakens the deterrent value of space law.
In addition, the OST primarily binds state parties, which means it does not directly regulate the activities of private or commercial military contractors. Article VI of the OST holds states internationally responsible for national space activities, including those conducted by non-governmental entities. However, the lack of specific guidelines for private actors involved in military applications of space technologies creates a grey area in practice. With the rise of privatized defense and dual-use technologies, this loophole allows quasi-military operations in space to proceed without adequate legal oversight or liability attribution.
The current body of space law consists of various treaties (e.g., OST, Rescue Agreement, Liability Convention), customary international law, and soft law instruments such as UN General Assembly Resolutions and the Guidelines for the Long-term Sustainability of Outer Space Activities. However, these sources are fragmented and poorly harmonized when it comes to military space use. There is no comprehensive regime or codified body of law that integrates disarmament, environmental protection, and security interests in space. As a result, states interpret their obligations inconsistently, contributing to legal uncertainty.
Due to these deficiencies, certain state behaviors, while clearly destabilizing, are not explicitly illegal. ASAT tests, for example, are a prime example of legally ambiguous conduct. Despite their risks to global space assets and their contribution to orbital debris fields, such activities remain largely unregulated. Similarly, the use of satellites for surveillance, targeting, and command-and-control during armed conflict may technically not breach any treaty, despite posing security threats.
NEED FOR REFORM AND GLOBAL CONSENSUS
To address existing legal gaps and prevent the escalation of conflict in outer space, scholars and institutions have proposed a range of reforms. Foremost among these is the adoption of a binding international treaty prohibiting all space-based weapons, including both kinetic and directed energy weapons. Additionally, the establishment of a global code of conduct for responsible behavior in outer space is essential. Such efforts must be supported by the creation of an independent, effective, and actively functioning monitoring and verification body—potentially under the auspices of the United Nations. Transparency and confidence-building measures (TCBMs) are equally crucial for fostering trust among spacefaring nations. Compulsory dispute resolution mechanisms and accountability measures should be promulgated as well as a comprehensive regime or codified body of law that integrates disarmament, environmental protection, and security interests in space.
Key forums for these discussions include the Conference on Disarmament and the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS). However, progress remains hindered by persistent geopolitical divisions. Space systems, particularly those involved in navigation, communication, and remote sensing, are integral to critical civilian infrastructure, notably in the energy and telecommunications sectors. These systems should therefore be dutifully maintained in order to efficiently support the delivery of essential services such as food supply, clean water, electricity, sanitation, waste management, and healthcare. Moreover, certain space systems are indispensable for the protection, safety, and maintenance of objects and persons and should be specifically protected under international law. Any disruption or destruction of such systems could have profound consequences for civilian populations and humanitarian efforts otherwise. Regardless of the nature of military operations conducted in outer space, they should remain subject to the constraints of existing international law. Such international law should in response, be made distinct and non-ambiguous, so as to not be subject to multiple interpretations.[7]
CONCLUSION
Military activities in space are an inevitable extension of terrestrial power politics, but their regulation remains weak and fragmented. While the Outer Space Treaty provides a framework that prioritizes peace, its outdated provisions and interpretive flexibility allow for strategic maneuvering. International space law must evolve to address the realities of 21st-century space operations, reinforce norms of peaceful use, and ensure that outer space remains a realm of cooperation rather than conflict.
REFERENCES
- Robert Wickramatunga, “The Outer Space Treaty” [Online] Available at: <https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introouterspacetreaty.html>
- Joseph Trevithick, Here’s Our Best Look Yet at Russia’s Secretive Space Cannon, the Only Gun Ever Fired in Space, The War Zone (Feb. 16, 2021). [Online] Available at: https://www.thedrive.com/the-war-zone/39277/heres-our-best-look-yet-at-russias-secretive-space-cannon-the-only-gun-ever-fired-in-spac
- Brian Weeden, 2007 Chinese Anti-Satellite Test Fact Sheet (Secure World Foundation, 2014). [Online] Available at: https://swfound.org
- Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025) [Online] Available at: https://www.icrc.org/en/law-and-policy/military-operations-space
- Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, Dec. 5, 1979, 1363 U.N.T.S. 3.
- Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025). [Online] Available at: https://www.icrc.org/en/law-and-policy/military-operations-space
- Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025). [Online] Available at: https://www.icrc.org/en/law-and-policy/military-operations-space#:~:text=The%20Outer%20Space%20Treaty%20recognizes,physically%2C%20such%20as%20cyber%20warfare.
[1] Robert Wickramatunga, “The Outer Space Treaty” <https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introouterspacetreaty.html>
[2] Joseph Trevithick, Here’s Our Best Look Yet at Russia’s Secretive Space Cannon, the Only Gun Ever Fired in Space, The War Zone (Feb. 16, 2021), https://www.thedrive.com/the-war-zone/39277/heres-our-best-look-yet-at-russias-secretive-space-cannon-the-only-gun-ever-fired-in-space (last visited July 21, 2025).
[3] Brian Weeden, 2007 Chinese Anti-Satellite Test Fact Sheet (Secure World Foundation, 2014), https://swfound.org (last visited July 21, 2025).
[4] Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025), https://www.icrc.org/en/law-and-policy/military-operations-space (last visited July 21, 2025)
[5] Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, Dec. 5, 1979, 1363 U.N.T.S. 3.
[6] Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025), https://www.icrc.org/en/law-and-policy/military-operations-space (last visited July 21, 2025).
[7] Military Operations in Space, International Committee of the Red Cross (Apr. 30, 2025), https://www.icrc.org/en/law-and-policy/military-operations-space#:~:text=The%20Outer%20Space%20Treaty%20recognizes,physically%2C%20such%20as%20cyber%20warfare. (last visited July 21, 2025).
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