Silent Signals: Electronic Warfare and the Legal Grey Zone

[Berfin Deniz Çabuk (Atty.) is a Ph.D. Candidate in Public International Law and Space Law at Utrecht University and a Research Associate in the Planet Stewards Project at the Copernicus Institute of Sustainable Development, Utrecht University]

Introduction

Electronic warfare has become one of the most effective and least visible tools of shaping contemporary security dynamics in outer space. By employing radiofrequency energy to disrupt or manipulate communications, states can interfere with critical infrastructure without firing a single missile. In outer space, this capability takes the form of electronic counterspace operations—techniques such as jamming and spoofing that target signals rather than physically destroying spacecraft. These methods operate in a legal and strategic grey zone: reversible, unexpensive, difficult to attribute. 

The vulnerability of even the most advanced satellite systems illustrates this challenge. The launch of the final GPS III satellite in March 2026 will complete the United States’ most substantial enhancement to its positioning, navigation, and timing (PNT) infrastructure in over a decade. With improved accuracy, stronger signals, and enhanced anti-jam capabilities, GPS III represents a major technological leap. Yet even these advanced systems remain vulnerable on the ground. In an era when financial systems, transportation networks, emergency services, and other critical civilian infrastructure rely heavily on uninterrupted satellite signals, interference can produce wide-ranging social, economic, and strategic consequences.

International law, however, has struggled to keep pace with these developments. The Outer Space Treaty (OST) explicitly prohibits the placement of nuclear weapons and weapons of mass destruction in orbit. Yet it remains silent on conventional weapons and emerging counterspace capabilities, including electronic attacks. The discussion then turns to general international law, particularly the prohibition on the threat or use of force under Article 2(4) of the United Nations Charter. But the question remains: does interference with satellite signals count as a use of force? As space systems become indispensable to both civilian life and military operations, these ambiguities are no longer theoretical.

This post argues that electronic counterspace operations expose a structural gap between technological capability and legal regulation. It first explains how jamming and spoofing work and why they are strategically attractive. It then examines the limits of the OST and the application of Article 2(4) of the UN Charter to signal interference. Finally, it explores the broader governance dilemma between soft law and hard law, arguing that a blended regulatory approach is urgently needed to prevent escalation in an increasingly contested space environment.

What are Electronic Counterspace Technologies?

Electronic counterspace technologies disrupt the signals that allow satellites to communicate with ground stations, rather than damaging the spacecraft themselves. The two main techniques are jamming and spoofing.

Jamming is an electronic attack that overwhelms legitimate radiofrequency signals by introducing noise into the same frequency band as the target signal. The interference temporarily blocks communication between satellites and receivers, whether affecting uplinks (signals sent to satellites) or downlinks (signals sent from satellites to users). Because jammers are often mobile and difficult to trace, attribution is challenging but the effects are reversible.

Spoofing is an electronic attack that takes interference a step further by broadcasting counterfeit signals that can deceive receivers or even hijack a satellite’s command and control system, potentially allowing attacker to manipulate its operations. It can target user receivers, causing misnavigation or service disruptions, or satellite command links, which can comprise satellite functionality more seriously. Spoofing is technically reversible, is difficult to detect, and hard to attributable. It is also inexpensive making it accessible to a wide range of actors, including non-state space actors. These characteristics pose unique challenges for accountability and legal regulation.

Understanding these techniques is key to appreciating why international space law struggles to address them.

Electronic Counterspace Technologies and the Outer Space Treaty

The 1967 Outer Space Treaty (OST) remains the foundational framework for regulating activities in orbit, yet it leaves significant gaps when applied to modern counterspace capabilities. While the treaty explicitly bans the placement of nuclear weapons and other weapons of mass destruction in orbit, it does not address conventional weapons or electronic methods such as jamming and spoofing.

Article IX further obliges states to exercise “due regard” for the interests of others, avoid harmful interference, and consult when activities may affect other states’ operations. If a state believes its activity could cause potentially harmful interference with another state’s peaceful use of outer space, it must undertake international consultations before proceeding. While this establishes a clear presumption of prior consultation and prohibits harmful interference, key terms like “due regard” and “harmful interference” remain undefined, and to date the consultation mechanism has not been used.

Moreover, the principle of peaceful purposes has long guided space law but its ambiguity and the different ways states interpret it weaken the OST’s practical effect. Over time, two main interpretations have emerged: the non-militarization doctrine, which calls for a complete ban on military activity in orbit, and the non-aggression doctrine, more widely accepted, which permits  military uses so long as they do not involve the threat or use of force under Article 2(4) of the UN Charter. Yet the absence of an agreed definition of a “space weapon” complicates efforts to draw legal boundaries, leaving unresolved the question of which forms of military activity in outer space may be considered permissible.

While the OST sets broad principles, these electronic operations also intersect with general rules on the use of force under international law, raising new legal questions.

“Use of Force” in Outer Space: Applying Article 2(4) of the UN Charter to Electronic Attacks

Building on the OST, Article III links its obligations to general international law. The treaty does not explicitly ban electronic attacks, but states are still bound by rules on the threat or use of force under Article 2(4) of the UN Charter. In this light, the travaux préparatories of the OST indicate that the reference to the UN Charter was intended to ensure that the exploration and use of outer space would not endanger international peace and security. Whereas, this creates a tricky tension: even when satellites are not physically damaged, interference with their signals can have serious consequences for civilian and military systems. Yet whether such signal level disruption counts as a “threat or use of force” remains unsettled.

Electronic counterspace operations can temporarily disrupt satellites, but the effects are often reversible and usually do not meet the legal threshold of a use of force. Article 41 of the UN Charter reinforces this point, clarifying that the “complete or partial interruption of… telegraphic, radio, and other means of communication” as measures not involving armed force.” Historical context, including the drafting the Charter during World War II, and state practice support the idea that signal interference is generally considered lawful.

In real-world practice, states rarely treat satellite jamming as a violation of Article 2(4). For example, Russia’s electronic warfare in Ukraine has occasionally interfered with third-country satellites, receiving an uncommon public criticism from the International Telecommunication Union (ITU) in 2024. The ITU’s Radio Regulations Board voiced strong concern over deliberate signal interference and noted that Swedish and French satellites were reportedly affected by activity traced to Moscow, Kaliningrad, and Pavlovka. Still, no state officially labelled these actions a breach of Article 2(4), showing just how much jamming exists in a legal grey zone.

Nevertheless, space is a unique domain. Some counterspace technologies could displace a satellite from its designated orbit, leading to its effective incapacitation or permanent destruction, thereby crossing the threshold of a use of force. In other words, the line between reversible signal interference and a full-blown use of force can be surprisingly thin, which is exactly why these legal questions are becoming more urgent.

Between Guidelines and Obligations: The Soft Law versus Hard Law

The absence of clear and binding restrictions on the deployment of counterspace technologies remains one of the pressing gaps in the space governance. This legal ambiguity complicates the maintenance of international peace and security: while binding treaty law provides predictability and stability, the rapid pace of technological innovation and geopolitical competition makes negotiating comprehensive new instruments increasingly challenging.

Against this backdrop, a range of non-binding initiatives seek to promote responsible behavior and mitigate risks associated with counterspace capabilities. These include the 2013 UN Group of Governmental Expert’s recommendations on Transparency and Confidence-Building Measures, the European Union’s proposed International Code of Conduct for Outer Space Activities, and the ongoing Open-Ended Working Group on the Prevention of an Arms Race in Outer Space under the United Nations General Assembly. Although these instruments are not legally binding, they help bridge regulatory gaps, foster mutual understanding, and establish norms. Over time, norms that gain widespread acceptance and consistent application can evolve into customary international law and eventually be incorporated into national law as binding obligations.

Yet their effectiveness ultimately depends on political commitment and consistent state practice, leaving unresolved questions about enforcement, responsibility and liability. Without complementary binding rules, today’s soft-law norms risk remaining aspirational rather than operational, highlighting the urgent need for an integrated framework that combines the predictability of hard law with flexibility of soft law.

Conclusion

Counterspace capabilities are not new, but today’s space environment is vastly different from the Cold War era. Today, space is crowded and highly contested, with a growing number of satellites being launched by commercial entities, regional powers, and private space companies. Modern electronic attacks are easy to deploy and are difficult to detect. Even reversible interference can disrupt  global communications, navigation, and emergency services, and in moments of tension, the line between temporary disruption and use of force is dangerously thin.

The interpretation of the principle of “peaceful purposes” remains unsettled, even though it lies at the heart of assessing the legality of such attacks. The Outer Space Treaty does not expressly prohibit electronic attacks, leaving their compatibility with the principles of “due regard” and “harmful interference” unresolved. This uncertainty is further compounded by the absence of a universally accepted definition of “space weapon” and the difficulty of distinguishing between military activities that constitute as non-aggressive uses of outer space and those that amount to use of force.

The vulnerability of even the most advanced systems—such as the GPS III constellation recently completed by the United States—illustrates that technological sophistication alone cannot eliminate risk. These realities highlight the broader dilemma of whether such risks should be governed through binding hard law or soft law.

Fortunately, humanity has not yet witnessed an armed conflict in space—but that does not mean one is impossible. These realities make one thing clear: the international community must urgently establish enforceable legal mechanisms to govern counterspace, combining the predictability of hard law with the flexibility of soft law to meet the challenges of an evolving space environment.