Beneath the Waves: Undersea Cables Become the Hidden Battlefield of AI Geopolitics

Garden-hose-thin fiber-optic cables buried beneath 12,000 feet of ocean carry 99% of all international data traffic. Yet these digital lifelines are increasingly becoming targets in a geopolitical chess game few people understand. In late 2024, Russian vessels cut multiple cables simultaneously in the Baltic Sea.

In early 2025, suspicious vessel movements near Taiwan prompted NATO investigations. The Red Sea witnessed cable damage coinciding with military conflicts. What was once dismissed as collateral damage from fishing accidents and ship anchors is now widely suspected as deliberate sabotage.

As artificial intelligence demands unprecedented data infrastructure, undersea cables transformed from boring telecommunications equipment into the frontline of great power competition. Nations are racing to control these networks, protect them from adversaries, and weaponize them as tools of geopolitical leverage.

The Critical Infrastructure We Can't See

The scale of undersea cable infrastructure is staggering. As of 2025, approximately 570 active submarine cable systems stretch roughly 1.5 million kilometers across the world's oceans, with 80 additional networks under construction.

These cables connect to over 1,700 landing points worldwide, forming an intricate web that carries an estimated $10 trillion in daily financial transactions alongside cloud data, military communications, and increasingly, AI training data.

Unlike power grids or roads, this infrastructure operates almost invisibly. Tech giants like Google, Meta, Amazon, and Microsoft own or co-invest in major systems. Between 2025 and 2027, investment in new undersea cables is projected to reach $13 billion, nearly double the previous three-year spending.

Meta's Project Waterworth alone will stretch 50,000 kilometers across five continents, making it the world's longest private cable system. Amazon's Fastnet will deliver bandwidth equivalent to 12 million simultaneous high-definition video streams.

This infrastructure expansion is driven by AI's insatiable appetite for data. Training advanced AI models requires moving massive datasets between continents at incredible speeds. Cloud services, video streaming, and financial systems depend on the uninterrupted flow through these cables.

Yet this dependence creates vulnerability. When cables fail, entire regions lose connectivity. When they're deliberately targeted, the impact extends far beyond telecommunications. It becomes national security crisis.

The New Sabotage Era: From Accidents to Alleged Attacks

Historically, undersea cable damage occurred through natural causes. Fishing trawlers with heavy equipment dragged across the seabed. Ship anchors accidentally snagged cables. Earthquakes and underwater landslides caused breaks. The International Cable Protection Committee reported 150 to 200 cable outages annually, mostly attributed to human accident rather than malice.

But recent incidents suggest a troubling shift in intent. Between November 2024 and January 2025, seven cables were cut in the Baltic Sea region alone. A Russian-flagged vessel called the Eagle S, suspected of being part of Russia's "shadow fleet," was detained by Finnish authorities in connection with damaged cables and power interconnectors.

The investigation raised a critical question: could a 100-ton anchor truly drag across cables without the crew noticing? Maritime experts and lead investigators suggest otherwise, pointing to deliberate sabotage over accidental damage.

The Baltic Sea represents Europe's "Achilles heel" for cable security. As a shallow body of water with an average depth of just 180 feet, cables lay closer to the surface and are more accessible to hostile actors. Four thousand ships pass through daily, providing cover for suspicious vessel movements.

Nine of the ten Baltic Sea nations are now NATO members following Russia's 2022 invasion of Ukraine, raising tensions further. This geopolitical powder keg has become a testing ground for hybrid warfare tactics that fall below the threshold of conventional war.

Similar patterns emerged elsewhere. In the Red Sea, undersea cables suffered cuts in 2024 and early 2025, coinciding with Houthi missile attacks on commercial shipping. While no direct causation has been conclusively proven, the timing raises alarm among security analysts.

In Asia-Pacific waters, unusual movements of Russian and Chinese surveillance vessels near Japanese and Taiwanese cable routes triggered NATO investigations into potential espionage or reconnaissance operations. The message is clear: undersea cables are no longer passive infrastructure. They're potential weapons in geopolitical conflicts.

The AI-Infrastructure Nexus: Why Hyperscalers Matter

Understanding undersea cable geopolitics requires understanding why technology companies, not governments, are the primary investors. Google's Pacific Connect Initiative involves multiple cable systems explicitly designed to connect Pacific island nations lacking digital infrastructure.

Microsoft, Amazon, Meta, and Google collectively dominate submarine cable investment because AI training, cloud computing, and data center operations require dedicated, high-capacity networks. These investments drive hyperscalers to participate in strategic partnerships with governments and international institutions.

This creates unusual alignment. When Meta invests billions in undersea cables, it's simultaneously pursuing commercial advantage and advancing national strategic interests. When the United States government helps subsidize cable routes to Pacific islands, it strengthens geopolitical relationships while advancing democratic values around digital infrastructure. China's aggressive cable investments in Asia and Africa have prompted Western nations to develop competing initiatives like the Blue Dot Network, which certifies infrastructure based on transparency, labor standards, sustainability, and cybersecurity.

The result is a fragmentation of global digital infrastructure along geopolitical lines. Western consortiums now intentionally avoid the contested South China Sea, routing cables through more circuitous paths at greater expense but with reduced geopolitical risk. Chinese companies are losing market share in international cable contracts.

Singapore and Japan are becoming critical hubs as nations seek geographic redundancy and reliability. The map of undersea cables is increasingly reflecting the "great divorce" between Western and Chinese technology ecosystems.

The Cascading Vulnerabilities: Physical, Cyber, and Strategic

Undersea cable threats operate across multiple layers. Physical attacks, whether accidental or deliberate, remain the most obvious danger. With only 100 cable repair vessels available worldwide, a coordinated series of cable cuts could create prolonged regional disruptions.

The 2024 South Africa incident, where multiple cable cuts occurred simultaneously, disrupted services across the continent for weeks because repair capacity simply didn't exist locally.

Cyberattacks represent an equally serious but less visible threat. Cable landing stations and the routers connecting undersea systems to terrestrial networks use standard network equipment vulnerable to unpatched software, firmware vulnerabilities, brute-force attacks, and social engineering.

A single compromised landing station could allow actors to intercept or manipulate data flowing through thousands of kilometers of fiber. While quantum computing remains theoretical, experts warn that once sufficiently capable quantum systems emerge, current encryption protecting cable traffic will become obsolete, potentially exposing decades of historical communications.

A third, often-overlooked threat involves strategic sabotage through supply chain compromise. The vast majority of submarine cable technology comes from a handful of manufacturers concentrated in a few countries. Export controls and sanctions against Chinese cable manufacturers like Huawei have created supply chain gaps.

When governments control cable supplier access, they effectively control which regions get connected and through which routes. This becomes leverage in international relations.

The Emerging Defense Infrastructure

NATO and participating nations are developing new frameworks to protect undersea cable systems. In 2024, NATO launched "Baltic Sentry," establishing multinational patrols and coordinated monitoring protocols. The International Telecommunication Union and International Cable Protection Committee established an International Advisory Body on Submarine Cable Resilience, developing best practices for risk mitigation and incident response.

Technological solutions include hybrid power-telecom cables that share costs and improve redundancy, increasing resilience by bundling electricity transmission with data capacity.

Route diversification has become a national security priority, with countries investing in alternative pathways that reduce dependence on critical chokepoints like the Strait of Malacca or the Red Sea. The U.S.-Japan Digital Security Alliance represents a cornerstone partnership focused on building trusted digital infrastructure aligned with democratic values.

Yet these defenses remain incomplete. Global supply chain concentration, limited repair capacity, and the geopolitically contested nature of key maritime regions mean vulnerabilities persist. As one cybersecurity expert noted, "The bigger threat seems to have been actually destroying the cables, accidentally or intentionally." This requires not just technological solutions but diplomatic coordination at levels rarely achieved in peacetime.

The AI Stakes: Why This Matters Beyond Cables

Undersea cables have become critical to AI development itself. Training large language models requires processing exabytes of data, necessitating reliable, high-capacity international connectivity.

A region cut off from global cable networks cannot participate in the AI revolution. Conversely, regions with abundant cable connectivity attract data center investments and AI talent. The geopolitics of undersea cables increasingly determines which nations will lead in AI and which will lag behind.

This creates strategic incentives for both protection and disruption. Nations view cable security as national security. Companies view cable investment as competitive advantage. The convergence of these interests produces an unprecedented surge in infrastructure investment, geopolitical competition, and security concern. The "honeymoon" period of the early internet, when technology united rather than divided, is definitively over.

For most people, the implications remain invisible. Data moves silently through fiber-optic cables beneath the waves. Financial transactions execute instantly. Cloud services render instantly. Yet the infrastructure enabling these conveniences sits at the intersection of great power competition, criminal opportunity, and technological ambition.

As AI demands expand, the stakes for controlling, protecting, and potentially weaponizing undersea cables will only increase. The future of global connectivity, economic stability, and AI development may ultimately be determined in the depths of the ocean, far from public view but never far from geopolitical calculations.

Fast Facts: Undersea Cables and AI Infrastructure Security Explained

What role do undersea cables play in AI infrastructure?

Undersea cables carry 99% of international data traffic and power cloud services, AI training systems, and data centers. These fiber-optic networks enable the massive data transfers required for training advanced AI models, making them essential to global AI development and competitiveness between nations.

How vulnerable are undersea cables to cyberattacks?

Cable landing stations and network equipment use standard infrastructure vulnerable to unpatched software, brute-force attacks, and social engineering. Additionally, quantum computing could eventually compromise current encryption protecting data in cables, creating long-term security concerns for sensitive information transmitted across undersea networks today.

What are nations doing to protect undersea cable infrastructure?

NATO launched "Baltic Sentry" patrols and coordinated monitoring. The ITU and ICPC established resilience guidelines. Countries invest in route diversification, hybrid power-telecom cables, and partnerships like the U.S.-Japan Digital Security Alliance to build trusted infrastructure and reduce dependence on geopolitically contested chokepoints.