In the early hours of November 17th and 18th 2024, subsea cables in the Baltic Sea – BCS East-West and C-Lion – reported faults. While the causes of these incidents are still being investigated, their timing and the surrounding circumstances have led to growing speculation that these could be more than mere accidents. European officials have raised the possibility that these faults were the result of deliberate actions, potentially aimed at exploiting vulnerabilities in critical infrastructure and sowing public fear. 

Given the rise of hybrid warfare tactics, the idea of using sabotage as a tool to destabilize nations or create confusion is a serious concern. Sabotaging critical infrastructure, such as subsea cables, could serve as a strategic maneuver designed to generate psychological pressure, disrupt communications, and undermine public confidence. While definitive conclusions cannot yet be drawn, the nature of these incidents raises important questions about the broader implications for global security and the resilience of subsea infrastructure. 

A Target in Hybrid Warfare 

Subsea cables form the backbone of global communications, transmitting approximately 95% of the world’s data. These vital links support financial systems, government operations, and internet access, making them attractive targets in hybrid warfare—where conventional and unconventional tactics blend to disrupt and destabilize. 

Even if the cable faults are proven to be accidents, the media’s amplification of such events can align with hybrid warfare goals. Whether intentional or accidental, such incidents draw immediate media attention, amplify public anxiety, and raise doubts about the security of critical systems—thus turning technical issues into broader societal concerns. 

The Strategic Role of Fear 

While the cause of these specific subsea cable faults is still under investigation, it is crucial for governments, industries, and the public to remain vigilant in the face of such potential threats. 

Securing our subsea networks is not just about preventing physical damage—it’s also about safeguarding against the broader strategic threats that aim to undermine confidence in the systems that keep us connected. 

Protecting Critical Subsea Infrastructure from Hybrid Warfare 

As subsea infrastructure—such as power lines, data cables, and pipelines—becomes increasingly vital, protecting these assets from intentional damage in hybrid warfare scenarios is essential. Key strategies include: 

1. Physical Monitoring and Detection: Real-time monitoring using advanced sensors, such as acoustic and seismic systems, can detect unusual activity around subsea infrastructure. These systems provide early warnings of potential threats, enabling timely responses to sabotage attempts. 

2. Digital and Data-Based Protection: Advanced technologies, such as Automatic Identification System (AIS) data-based solutions, can play a key role in protecting subsea infrastructure. These systems monitor maritime traffic in real-time, enabling the detection of vessels on a collision course with critical subsea assets. By analyzing vessel movements and providing predictive alerts, AIS-based tools allow for proactive measures, such as rerouting vessels or dispatching patrols to intervene before damage occurs. 

3. Surveillance and Patrols: Drones, autonomous underwater vehicles (AUVs), and remotely operated vehicles (ROVs) enable effective surveillance of vast subsea areas, identifying unauthorized tampering or damage to infrastructure. 

4. Physical Protection: Subsea infrastructure can be physically protected by burying cables, armoring pipelines, or using reinforced materials to prevent damage from anchors, fishing nets, or direct attacks. Creating redundant routes for cables and pipelines also ensures operational continuity if one is disrupted. 

5. Cybersecurity: Protecting the control systems of subsea infrastructure from cyberattacks is vital. Strong encryption, secure authentication, and regular cybersecurity audits can mitigate malicious attempts to disable or manipulate these systems. 

6. International Cooperation: Given the global nature of subsea infrastructure, international legal agreements are essential for protecting these assets from state-sponsored attacks. Joint defense initiatives and intelligence sharing between nations and private-sector stakeholders also strengthen overall security. 

7. Rapid Response Teams: In the event of an attack, rapid response teams equipped with remotely operated vehicles (ROVs) and trained divers can quickly restore damaged infrastructure, minimizing operational downtime and preventing further exploitation. 

The Broader Picture 

Whether these recent incidents were deliberate or accidental, they highlight the vulnerabilities of subsea infrastructure in an era of hybrid threats. By combining technological, physical, and diplomatic strategies, we can strengthen the resilience of subsea infrastructure against hybrid warfare, ensuring the continued stability of critical global systems. Safeguarding subsea networks is about more than preventing damage—it’s about fortifying trust in the systems that underpin our interconnected world. 

Authored by

Ulrik Høy-Petersen
Sales Manager & Retired Danish Navy Commander