The global internet backbone rests on a fragile network of subsea cables, and the world is sleepwalking toward catastrophe. Recent incidents, from suspected sabotage in the Baltic Sea to geopolitical tensions over cable routes, reveal a structural vulnerability that no one is raising: the lack of a unified international framework to protect these critical assets. As nations weaponise interdependence, the hidden cost could be the collapse of global communications.

Consider the Baltic Sea, where in October 2023, damage to the Estlink 2 power cable and two data cables sparked fears of Russian sabotage. Investigators found anchors dragged across the seabed, but no culprit was named. Meanwhile, in the Red Sea, Houthi rebels threatened to target cables, forcing rerouting and highlighting the choke points. These are not isolated events. They are symptoms of a systemic failure: subsea cables are owned by private consortia, regulated by outdated treaties, and guarded by navies that cannot police every mile of ocean.

The concern no one is raising is the absence of mandatory redundancy or backup routing. Most global internet traffic flows through less than 20 major cable routes, with chokepoints like the Red Sea, the Strait of Malacca, and the English Channel. If a single cable is cut, traffic reroutes, but if multiple are severed simultaneously in a coordinated attack, the internet fragments. The 2023 Tonga volcanic eruption proved that isolation can last weeks.

There is no global body with authority to enforce protection. The UN Convention on the Law of the Sea (UNCLOS) offers vague protections but no enforcement. Private cable owners are left to negotiate with governments, who increasingly treat cables as intelligence assets. The US has warned about Chinese cable ships mapping ocean floors; China accuses the US of spying via cables. The trust deficit means no one agrees on a shared defence strategy.

The economic cost is staggering. Goldman Sachs estimates that a two-week internet blackout in the US could cost $30 billion. For developing nations dependent on a single cable, the cost is existential. Yet, there is no public debate about requiring cable operators to build diverse routes or to invest in satellite backup. Starlink and other low-earth orbit satellite systems offer hope, but they cannot carry the full load of global data and are themselves vulnerable to cyberattack.

The structural failure is not just technical but political. Nations view cables through the lens of sovereignty. Russia has invested in its own cable systems to bypass Western hubs, while the US blocks Chinese companies from laying cables. This fragmentation undermines the collective resilience. The hidden secondary consequence is the erosion of the internet's neutrality: as cables become pawns in great-power competition, ordinary citizens bear the cost of slower, less reliable connections.

We need a new multilateral agreement that designates critical cable routes as international infrastructure, with rights of passage and protection, akin to international straits. We need a fund to subsidise redundancy for developing nations. And we need an independent body to monitor threats and coordinate responses. Without these steps, the next cable cut will not be a mere disruption but a fracture of the global system.

Barnaby Finch, reporting from London. The silence from regulators is deafening.