The underwater geopolitics of the internet

Researched by: Nirmal Bhansali

Wtf is a subsea cable?

With all the talk about ‘the cloud’, many people assume that their data travels through air. But it actually moves across the world along undersea cables placed on ocean beds. Here’s how these cables work:

The cables begin as a cluster of strands of tiny threads of glass fibers. Lasers propel data down the threads at nearly the speed of light, using fiber-optic technology. After reaching land and connecting with an existing network, the data needed to read an email or open a web page makes its way onto a person’s device.

Their total length: Nearly 1.4 million kilometres. See the map for Asia/Europe below:

A bit of trivia: The first ever undersea cable was laid in 1858—and it connected England to the United States via telegraph. Queen Victoria sent the first congratulatory message to then US President James Buchanan. It took 17 hours for the message to reach him. 

Lightning speed: Data travels at the speed of light along these cables, or as the New York Times puts it: “The data zips from New York to Sydney, from Hong Kong to London, in the time it takes you to read this word.” The fastest is a transatlantic cable called Amitié—funded by Microsoft, Meta et al. It can carry 400 terabits of data per second: “That's 400,000 times faster than your home broadband if you're lucky enough to have high-end gigabit service.” And it’s only as thick as a garden hose.

The big takeaway: There are 500 active and planned undersea cables—which transport 99% of the world’s data. Financial transactions worth more than $10 trillion are transmitted via these cables every day. Any damage to these cables can cause unimaginable havoc.

Ok, who controls them?

Consortiums of tech and state-owned telecoms companies build these cables—and bandwidth on them to customers around the world. For example: SeaMeWe-5, which connects France, Indonesia, Italy, Saudi Arabia, and Turkey, is owned by more than a dozen companies, among them China Mobile and Telecom Italia Sparkle. And maintaining them requires a high level of cooperation—even among hostile nations:

[B]ecause of complex, long-standing maintenance agreements, often countries’ most sensitive, critical infrastructure is being repaired by adversarial nations. A fault last year on a major intercontinental fibre cable owned by US carriers AT&T and Verizon, among others, was repaired by Chinese engineers operating from a Chinese vessel.

But that fragile truce is now fraying—under pressure from geopolitical rivalry—specifically between the US on one side—and Russia and China on the other.

Fear of espionage: Washington has grown increasingly worried about all-pervasive Chinese tech—which is built into critical parts of the world’s infrastructure. It has therefore tried to muscle out Chinese companies from the ownership of undersea cables. The US blocked a partnership between Amazon, Meta and China Mobile to lay a cable connecting California to Singapore, Malaysia and Hong Kong. In fact, it was so paranoid that it withdrew permission for the project even after the Chinese dropped out—and even though most of the 12,000 km cable had already been built. 

Data point to note: According to a Financial Times analysis, Washington’s campaign has been a huge success: Chinese supplier HMN Tech has provided or is set to provide the equipment to only 10% of all existing and planned global cables. In comparison, French cable maker ASN has supplied 41% and American company SubCom has supplied 21%.

But why does any of this matter?

The global demand for cables will grow exponentially as the world goes digital. But new projects are stalling out due to geopolitical rivalry. Washington has blocked four cables that would have connected the US and China—while Beijing drags its feet in approving any project that runs through the South China Sea. Here’s an example closer to home: 

India’s Global Cloud Xchange… also owns the massive FALCON cable that connects India, Iran, Iraq, Kuwait, the Maldives, Sri Lanka, Oman, Saudi Arabia, the United Arab Emirates, Qatar, and Yemen. If Iran and Saudi Arabia’s new, China-brokered friendship were to fray, one of the partners might, say, delay approval of a new cable. That matters because subsea cables use well-trodden paths: It’s easier to lay a new one next to existing ones than to forge new paths on the seabed.

Who gets left out: If the Cold War extends below the seas, it may leave many nations isolated—just because of their geographical location:

Subsea cables, in fact, stand to become a new Iron Curtain. Countries will be directly connected with friendly countries by cables traveling through friendly waters. That means countries in more challenging parts of the world that can best be reached through the waters or exclusive economic zones of an unfriendly country may not see a lot of new cable investment. With economies moving toward more and more digitalization, being left out of the new and better pipelines would be a great pity for the countries that have the misfortune of belligerent neighbors.

Point to note: Smaller nations have already become collateral damage. In 2021, the World Bank scrapped a cable project it was leading to connect three Pacific island nations. The reason: It was pressured by the US not to award the contract to the Chinese company HMN Tech.

Also a worry: Until now, undersea cables have not been a battle target, but that could change in the future—especially since it doesn’t take much to cut a wire:

The explosive sabotage last year of the Nordstream 1 and 2 natural gas pipelines connecting Russia and Europe was much more logistically difficult than cutting an internet cable the thickness of your thumb. An ally of Russian leader Vladimir Putin said subsea cables are fair game for attack. Taiwan has 27 subsea cable connections that the Chinese military could see as tempting targets in an attack.

Cutting key cables would put the entire global telecommunications system in jeopardy.

The Red Sea example: There are 16 cables that travel through the Red Sea—and carry 17% of the world’s internet traffic. It is the key underwater route that connects Asia and Europe. One of these is the Asia-Africa-Europe-1 internet cable that travels from Hong Kong to Marseille, France–providing internet connections to more than a dozen countries, from India to Greece. Any disruption to this cable would be disastrous. When it was briefly severed in 2022, seven countries were affected. Ethiopia lost 90% of its connectivity, and Somalia 85%.

The bottomline: We leave you with this quote from a leading foreign policy expert:

One of the big risks right now is heading in the direction of bifurcated networks. Does this create a system where you don’t have connectivity, with a quasi-cold war, eastern bloc versus the west? I don’t think we’re there yet . . . but I do worry that’s the direction we’re headed in.

Reading list

CNET has the most comprehensive primer on subsea cables. Two of the best reads on the effects of geopolitical rivalry are sadly behind a paywall: Financial Times and Foreign Policy. Wired has a very good piece on why everyone should worry about Egypt—all those sixteen undersea cables have to travel through the country to reach the Mediterranean. Rest of World looks at how tech giants like Google and Meta are vying to build cables that connect Africa—but also control it. Inkstick looks at the India angle including players in the undersea cable game—Airtel and Jio