Moisés Naím / El País

It’s easy to imagine the Internet as an ethereal, immaterial entity. We go about our days connecting to wireless networks and storing our data in the "cloud" with the reasonable assumption that our information is safe as it flows from one part of the world to another.

Unfortunately, that’s mostly wrong. The global network on which we so depend is alarmingly physical and eminently vulnerable. According to Air Marshal Edward Stringer, former director of operations for the British Ministry of Defense, 95 percent of all international data traffic passes through a small number of undersea cables. We're talking about roughly 200 cables, each the thickness of a garden hose and capable of transferring about 200 terabytes per second.

This very physical network processes some 10 trillion dollars worth of financial transactions every day. And, as Stringer explains, in the last 20 years Russia has invested heavily in systems capable of attacking this network of underwater cables. The Kremlin today has a fleet of sophisticated unmanned submersibles designed specifically for this purpose. So does China.

This isn’t some hypothetical threat. As recently as October 2022, an undersea cable connecting Scotland’s Shetland Islands to the rest of the world was severed at two points. A few days prior, a Russian “scientific research” ship was detected in the area. Unfortunately, it’s not possible to prove that Russia cut the cable. In fact, most of the time, outages are due to accidents with fishing trawlers or seismic events on the seabed. Even so, the coincidence alarmed the Western powers’ security agencies, who perceived the incident as a warning from the Kremlin. Another relevant event was the decision taken in February 2023 by the two largest Chinese telecommunications companies, who decided to withdraw from the international consortium that is developing a 19,200 km network of submarine cables connecting Southwest Asia and Western Europe.

The impacts of a coordinated attack against these undersea cables would be incalculable. Such an attack would cripple global trade, banking and finance, and telecommuting, not to mention the technology and communication industries as a whole, and would likely trigger an instant global recession. But the impact would go far beyond the financial. Supply chains in the 21st century depend on the constant transfer of data to coordinate the delivery of goods and supplies. The interruption of this data flow would cause a domino effect of delays and failures, which would restrict the economic, political and even cultural integration of different geographical areas.

Furthermore, the financial and economic crisis that such an attack would precipitate would not even be the biggest problem. “Disconnecting” the cables of rival powers, would lead to an unmanageable geopolitical crisis, especially if the responsibility can be attributed to a specific state actor, provoking conflicts and reconfiguring alliances. Countries that rely heavily on digital infrastructure would be hardest hit, while those with autonomous communication and technology capabilities would gain a strategic advantage.

Such scenarios should not be ignored, because anarchy reigns on the high seas. Existing international treaties do not satisfactorily cover the case of undersea cables. This is emblematic of a global system

that—despite being of incredible public importance—is not adequately protected either physically or legally. Until now, maritime powers have refrained from attacking undersea infrastructure on a large scale. That’s because attacking an opponent's cables and submarine connections would provoke costly retaliation. But the current equilibrium is unstable and inherently susceptible to disruptions that could destabilize the world system overnight.

When we imagine the events that could spark an escalation between the West and its rivals, we tend to forget this reality. Much like blood in the body, contemporary societies cannot function without the data that circulates through the Internet, which currently flows through an infrastructure that is extremely difficult to defend.

The West's sense of invulnerability is illusory, and its rivals understand that certain infrastructure choke points—such as undersea cables — are its Achilles heel. This reality underscores the need to maintain minimally functional relationships on the international scene.

Interdependence between countries is not just a concept bandied about by diplomats. It is a reality that defines the world today. This is a world in which problems, risks, and threats become increasingly international while government responses remain predominantly national. There are many problems that no country can solve alone. The need to coordinate our actions and collectively respond to threats is a challenge for which the world is not ready.