Depths of Deception: State-Backed Undersea Cable Disruptions and the Role of International Maritime Law

Written by Kyle Patlove

Introduction & Background

In just the past 18 months, a pattern of undersea cable disruptions,¹ six in the Baltic Sea and the Taiwan Strait alone, has coincided with the presence of large cargo ships linked to Russia or China.² These cuts mirror broader incidents across the region; NATO officials now cite at least eleven such disruptions between mid‑2023 and early 2025.³ Carrying 98–99 percent of international internet traffic, these submarine cables are the literal global economic lifeline.⁴ What may seem like isolated maritime accidents are now increasingly viewed as elements of hybrid warfare. Scholars and senior NATO leaders alike now argue that these are deliberate attacks on the digital infrastructure of NATO-aligned states.⁵ Before Russia’s 2022 invasion of Ukraine, the UK’s outgoing Chief of Defence Staff warned that such sabotage could constitute an “act of war.”⁶

NATO’s strategic posture has since adapted in response. In January 2025, it launched the “Baltic Sentry” initiative to enhance maritime surveillance across Europe,⁷ signaling a recognition that such incursions pose serious threats to alliance security.⁸ Further, the conduct of Chinese research institutes has done little to dispel further suspicion. In January, Newsweek reported that engineers at Lishui University in Zhejiang had filed a patent application for a “dragging-type submarine cable cutting device,” ostensibly for use in “emergency situations,” a rationale that a Norwegian cable expert has dismissed as “absurd.”⁹

To date, no coherent legal counter‐doctrine has emerged to treat cable sabotage as specific armed aggression or to authorize NATO or allied states to detain, investigate or respond diplomatically or militarily below the collective defense Article 5 threshold.¹⁰ As the national defense and legal scholar Dr. Jill Goldenziel has argued, the existing frameworks, primarily the United Nations Convention of the Law of the Sea (“UNCLOS”) and the 1884 Cable Convention, fail to provide coherent authority for prevention, deterrence, or proportionate response in cases of suspected cable sabotage, as “only the flag state of the alleged perpetrator vessel or the state of nationality of an alleged perpetrator has jurisdiction to investigate and prosecute cable incidents.”¹¹ Yet, existing scholarship often stops short of articulating viable reforms.

This piece advances a hybrid solution, building on the work of Sophia Besch and Erik Brown, who advocate for the development of an enforcement regime based on shared jurisdiction, cable protection zones, and public-private coordination.¹² As they rightly note, “[t]here is not a single regulatory regime for protecting subsea data cables,” and continuous military patrols are these waters is simply impractical.¹³ Instead, by leveraging existing treaties and emerging legal tools, NATO can adopt a layered strategy: incorporating UNCLOS into domestic law, creating binding liability mechanisms, and equipping the alliance with legal and operational means to protect undersea infrastructure. Only then can NATO address the legal and strategic gaps that leave these critical systems exposed.

Analysis

As with most matters in the arena of international maritime law, assessing the legality of Russian and Chinese cable-cutting operations begins with the UNCLOS. Two provisions are particularly relevant:

Article 112

Right to lay submarine cables and pipelines

1. All States are entitled to lay submarine cables and pipelines on the bed of the high seas beyond the continental shelf . . . .

Article 113

Breaking or injury of a submarine cable or pipeline

Every State shall adopt the laws and regulations necessary to provide that the breaking or injury by a ship flying its flag or by a person subject to its jurisdiction of a submarine cable beneath the high seas done wilfully or through culpable negligence, in such a manner as to be liable to interrupt or obstruct telegraphic or telephonic communications, and similarly the breaking or injury of a submarine pipeline or high-voltage power cable, shall be a punishable offence. This provision shall apply also to conduct calculated or likely to result in such breaking or injury. However, it shall not apply to any break or injury caused by persons who acted merely with the legitimate object of saving their lives or their ships, after having taken all necessary precautions to avoid such break or injury.¹⁴

These provisions establish both a positive right of states to lay submarine cables and a negative obligation not to damage them.¹⁵ However, enforcement remains severely constrained. UNCLOS Article 110, governing the “right of visit,” permits states to board foreign vessels on the high seas only under narrowly defined circumstances: suspicion of piracy, slave trading, unauthorized broadcasting, or when the vessel is stateless.¹⁶ Cable sabotage does not fall within any of these categories. As a result, perpetrators operating under a national flag retain de facto immunity from interdiction or inspection by other states, unless their actions rise to the level of piracy, a threshold that is practically difficult to meet. Accordingly, NATO states presently lack both a comprehensive legal framework for pursuing claims related to cable sabotage and a reliable forum in which to adjudicate them. To address this, NATO states should adopt or amend domestic laws to allow for negligent or willful damage to undersea cables, and advocate for an amendment to UNCLOS Article 110 to extend the “right of visit” to cases of suspected cable sabotage.

Domestic codification of these obligations is not merely symbolic. It would create enforceable standards by which perpetrators, whether state actors, state proxies, or private entities, could be held legally accountable, even in their physical absence. Civil proceedings initiated under national laws, grounded in the prohibitory language of UNCLOS and enhanced by NATO-aligned legal coordination, would allow for the pursuit of liability, the freezing of assets, and the imposition of fines or damages on responsible entities. While actual enforcement against foreign state-linked actors may prove difficult in the short term, the ability to secure formal judgments, especially those backed by coordinated sanctions or recognition across allied jurisdictions, would send an important message. Legal findings of culpability, even issued in absentia, delegitimize such reckless conduct, enable reparations claims, and create a lasting evidentiary record that could support future diplomatic, economic, or military responses. With significant Russian capital already frozen up in U.S. and European markets, such action would serve as a potent deterrence mechanism against Russian-backed offending vessels.¹⁷

Conclusion

This form of legal infrastructure would serve as both a deterrent and a framework for escalation management. By clearly defining cable sabotage as a punishable offense under both domestic and international law, and by empowering NATO members to act in concert when such infrastructure is attacked by extending the “right of visit” to cases of suspected cable sabotage, the alliance would finally possess a doctrine capable of responding below the collective defense Article 5 threshold without defaulting to ambiguity or inaction.

Posted in Blog

Written by Kyle Patlove

Share this post

Contact Us

Join Our Mailing List