A new rivalry between the U.S. and China over the world’s undersea cables

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(Interactive Submarine Cable Map courtesy of TeleGeography)
(Interactive Submarine Cable Map courtesy of TeleGeography)

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Thousands of miles of fiber optic cable lying at the bottom of the world’s oceans carry more than 95% of the world’s data, from phone calls and emails to encrypted military secrets.

Now, those submarine cable systems are at the forefront of a new rivalry between China and the U.S. over who controls the flow of big data.

"Undersea cables ... have now become a weapon of war in this new Cold War between China and the U.S.," Reuters reporter Joe Brock says.

Today, On Point: The new battle over undersea cables.

View: An interactive map of a submarine cable system

Click the image below for a closer look at a submarine cable map. 

(Submarine Cable Map courtesy of TeleGeography)
(Submarine Cable Map courtesy of TeleGeography)


Nicole Starosielski, professor of media, culture and communication at New York University. Author of The Undersea Network.

Joseph Keller, visiting fellow at the Brookings Institution’s Center for Security, Strategy, and Technology.

Also Featured

Rick Chislett, former manager of splicing and testing for IT Telecom.

Steve Arsenault, director of Global Subsea Solutions for IT Telecom.


MEGHNA CHAKRABARTI: The Internet's true circulatory system lies deep underwater, nearly 900,000 miles of fiber optic cables snake across ocean floors, transporting the world's information, financial transactions, military and diplomatic traffic. American firms have dominated the cable laying business since the start.

But now China is entering the scene with one of the world's most advanced and far-reaching subsea cable networks. It's a $500 million undersea fiber optic cable that would link Asia, the Middle East and Europe, and it snapped the United States to attention. Here's Republican Congressman Brian Mast of Florida in March, speaking about the bipartisan undersea cable Control Act which passed the House.

BRIAN MAST: Chinese companies heavily subsidize, of course, by the PRC. The communist government have started investing heavily in owning and supplying subsea cables. Think things like voice communications, data, internet, trillions of daily international financial transactions, things that you don't want China getting a hold of.


They weaponize every bit of social media that they can. They try to make these capabilities fit their own nefarious ends. So do we really think for a second that they would not do the same with undersea cables? I'm not going to be fooled into thinking that.

CHAKRABARTI: The Chinese cable counted telecom giant Huawei Technologies as one of its shareholders. Robert Spalding of the Hudson Institute told Bloomberg News that's a cause for concern.

ROBERT SPALDING: In Canada, for example, we've seen data be rerouted to China. We've also seen, for instance, what happened with the African Union. So it's clear that Huawei has a pattern of behavior that shows data being moved to China.

CHAKRABARTI: However, you won't hear such bellicose talk from Europe because France and Germany have already said they will not isolate China or diplomatically disparage Beijing. Despite the risks feared by the United States. This is Emily Taylor of Oxford Information Labs.

EMILY TAYLOR: You don't take unnecessary risks. But there are many risks associated with taking a nationalistic view to technology. It can potentially break the architecture of the Internet.

CHAKRABARTI: The U.S. and China are already deep into a power struggle that will define the future. It's a race for silicon chips, rare earth minerals, 5G technology, artificial intelligence, space exploration, navies and air forces, consumer products and cultural influence. Now, as some have put it, there's a war under the waves.

So how should we best understand the rising tensions over China's new undersea fiber optic cables, not just from the U.S. perspective, but ... the world? Well, Nicole Starosielski joins us. She is a professor of media culture and communication at New York University and an expert in undersea fiber optic cables. She's author of the book The Undersea Network. Nicole, welcome to On Point.

NICOLE STAROSIELSKI: It's great to be here.

CHAKRABARTI: Also with us is Joseph Keller. He's a visiting fellow at the Brookings Institution's Center for Security Strategy and Technology. Joe, welcome to you.

JOSEPH KELLER: Thanks so much for having me.

STAROSIELSKI: So first, let me have you both describe really the extent and importance of these undersea fiber optic cables. I mean, Nicole, I understand that they carry, what, 95 to 99% of the world Internet traffic.

STAROSIELSKI: Yes. When the Internet goes between continents at large, the 99% of the time, over 99% of the time goes on the very bottom of the seafloor on undersea cables. They're integral to global communications. We don't have the Internet as we know it today without them.

CHAKRABARTI: Okay. And, Joe, as I said earlier, the United States and U.S. companies have basically had the lead on laying cable for a long time now. But describe a little bit more about how the networks work. Does it mean that those companies essentially control what traffic goes through those cables?

KELLER: Yes. So stakeholders come together to try to make investments in some of these telecom projects. They involve ten, 12 individuals. It requires participation, cooperation between countries, between governments and between companies, even though they do not share the same regions.

CHAKRABARTI: So, Nicole, I guess what I'm trying to understand before we get deep into what China is doing, is, you know, trying to put the concerns that we heard in the intro say, for example, Congressman Brian Mast, into context for right now. With all those basically U.S. owned cables, are those U.S. tech companies then deciding what traffic goes? Where could they do the same things that the United States is accusing China of potentially doing with its fiber optic undersea cable?

STAROSIELSKI: I think the threat is a little overstated. Well, certainly anyone who owns a subsidy cable system could halt all the traffic on that cable system, monitor all the traffic on that cable system. That's not what they choose to do, because that wouldn't be economically viable. That wouldn't be politically viable. There are a lot of reasons that the system remains open as it is today.

CHAKRABARTI: Okay. So does that mean that it would remain open and you believe it would remain open with China's cable connecting what, Asia, the Middle East and Europe?

STAROSIELSKI: I believe that that would be an open system that has traffic transiting it in the same way that many other cables around the world do.

CHAKRABARTI: Okay. So we'll talk more about that in a few minutes because, I mean, clearly, we're doing this hour because not everyone was as confident. ... I want to hear from both of you about China's new fiber optic cable. It's called SeaMeWe-6. What should we understand about it?

KELLER: So this has been a very provocative issue. So earlier this year, around February, construction for a cable from France to Singapore, I think is emblematic of these rising U.S.-China tensions, because mainly reports suggest that the U.S. has been sabotaging telecom deals like this with China for years.

CHAKRABARTI: Tell me more.

KELLER: So reports suggest that this is one of at least six private undersea cable projects that have come together over the Asia-Pacific region. ... It links a lot of territories, including landing stations on the continent of Africa. The thing here, though, is that several years ago when the project came together, the consortium of stakeholders agreed that the entity laying the cable, the fiber optic cable, would be a Chinese associated company.

But given the threat that U.S. proceed from associated Chinese companies laying the cable and foreign adversaries, they decided to undertake what has been seen as an influence campaign behind the scenes, providing favors, for example, through grants, training grants and money for individuals involved in participating the stakeholders to get them to flip their decision.

So individuals had decided that verbally we would go with a Chinese cable later, this case called HMN Tech. After this influence campaign, individuals for many reasons decided they would go with a U.S. backed cable, their entity called Subcom. So that's where we are today. A story that started several years ago with a larger influence of Chinese backers and stakeholders now has a greater influence in the U.S. and in the intervening time.

Stakeholders from China have left that project and have struck out on their own to try to construct what has been seemingly seen as competing and reactionary cables at the same time along similar routes.

CHAKRABARTI: Okay, Nicole, do you want to add to that? Because this seems to be, you know, kind of both a diplomatically complex and even technologically complex story that's unfolding.

STAROSIELSKI: Yeah, I would just say that the ... initial subsea cable system had members of many countries involved, not just China. And that these systems are typically, have typically been, what are called consortium systems. So there are consortia that have, you know, the United States, U.S. based companies, France based companies, China based companies all collaborating together to lay this global kind of international projects.

And so I think that it's important to keep that context in mind, that there's been a lot of collaboration in the industry and that this hasn't typically been something that governments have stepped in to moderate that international collaboration in the way that they're strongly doing now.

CHAKRABARTI: Governments being, I mean, specifically the United States stepping in?

STAROSIELSKI: Specifically, the United States. There's always been a role for government, but this kind of action we've not seen before.

CHAKRABARTI: Okay. Joseph Keller, do you want to add to that?

KELLER: No, I think Nicole hit it right on the head. What is essential here is the collaboration between countries, between governments, because of the landing points of these cables. Permission is required for projects to go forward. And generally, all stakeholders stand to benefit from productive and successful execution of these projects. But given the specific stance that the U.S. has against China. It is creating tensions and difficulties for all projects that involve China, even for those who are not directly affiliated with it.

CHAKRABARTI: Okay. Now, Nicole, I think Joe had mentioned this a minute ago, that the U.S. has actually forced changes in fiber optic cable routing on several other projects in the Asia Pacific region over the last several years. Did I hear that correctly?

KELLER: That's right.

CHAKRABARTI: Does that mean, Nicole, that there are miles and miles of undersea fiber optic lying around, not being used right now?

STAROSIELSKI: Well, they were not constructed in the way that they had initially been planned, either to China, Chinese territory or by Chinese suppliers.

CHAKRABARTI: Okay. So because the United States successfully just stopped the completion of those particular cables ... is SeaMeWe-6, the project that's really gotten all this public attention ... still going forward?

KELLER: It is still going forward. You mentioned this at the top. It's expected to be finished around 2025. And so this is a project that has been successful going forward, just without those Chinese stakeholders.

MEGHNA CHAKRABARTI: Steve Arsenault is director of Global Subsea Solutions for IT Telecom, a Canadian fiber optic cable laying firm. And he says people don't realize that much of what they do on the Internet travels on the ocean floor.


STEVE ARSENAULT: There is no doubt that a misconception exists that global communications are somehow facilitated by satellites. I mean, it's funny to me because, you know, you ask anyone, you know, what, this signal path takes for a given trans-oceanic phone call, and almost no one will tell you that it's through an underwater cable. But the fact remains, there are literally thousands and thousands of kilometers of cable underwater just lying there.

CHAKRABARTI: Rick Chislett also works for IT Telecom, he spent 41 years on its cable laying ships as the manager of splicing and testing. He's semi-retired in Windsor, Nova Scotia, now, but he'll be back out on the ocean off the coast of Denmark in a couple of days. So we asked him, what's it like laying fiber optic cable around the world?

RICK CHISLETT: My responsibility was managing the splicing and testing on board. I also look after the loading of the vessels just to make sure that the cable is stored in a hole and in the correct manner. Today, I checked the crew manifest and onboard our ship right now there are 50 crew members. And they are in transit to load cable. And then it will proceed to Denmark. And in Denmark, there is more cable to be loaded. They will be testing and jointing.

On some projects when we lay close to shore where cable can become damaged by fishing anchors, we will need to bury it. And we use what we call a subsea plow. And we tow this behind the vessel. Plow weighs roughly about 30 ton. The cable will leave the ship, go down to the seabed, go through the plow and out the back end of the plow. I will create a trench depending on the seabed conditions, soft or how hard it is, it could be carried to a maximum of two meters.

We were on a particular project about three years ago, off the west coast of South America and the bottom conditions off the coast is very mountainous. And we were toeing the sea plow behind us. We came to an area where it was a downslope and normally on downslopes, our survey team are able to identify them, and the C-Plow operators are able to slow it down.

But for some reason it didn't slow it down fast enough. It overran the cable, and it damaged the cable at that time. The plow overturned on its side, so the ship came to a complete stop. The cable damage was repaired in probably I think about 20 hours, and the plow damage took about two days.

We do get a lot of people who spend a lot of years out on the water and enjoy it. The ship crew becomes something like a family, you know. Everybody gets along and that kind of thing. And you have to because you're on a vessel that's only 115 meters long. Food is good. Which is always great. For me, I worked for 40 plus years at this business. And I feel that I helped to connect families together, people together from country to country. I feel good about contributing that to the world. And I have to say, I've worked all over the world.

CHAKRABARTI: I'd like to actually see if we can clarify some of the murky relationships here. To use a marine pun, if I could, that are needed in order to lay these cables and operate them. Because I have to say, I'm still not entirely certain how the United States managed to interfere with the laying of this new Chinese cable.

So, Joe Keller, let's go back to April 2020 and the Trump administration, when the Trump administration signed an executive order that formalized something called the Committee for the Assessment of Foreign Participation in the United States telecom services sector. Now, it's informally known as Team Telecom. What does team telecom do?

KELLER: I'm really glad you took the chance to describe that. This is an interagency group that's run by the U.S. Department of Justice that makes recommendations to the Federal Communications Commission about the cables that are going to be landing on U.S. soil.

CHAKRABARTI: Landing on U.S. soil. Okay, but Sea-Me-We 6 is not landing on U.S. soil.

KELLER: Correct. But I think the U.S. has taken an increasingly aggressive stance. So not only for cables that are physically on U.S. soil, but also for cables that have in direct connection to the U.S. through other countries and through other infrastructure. So the U.S. has this distrust of Chinese technology, Chinese infrastructure. And I think there's greater and greater steps taken by Team Telecom and other measures acknowledging the increasing competitiveness with China, but also trying to distance themselves by any association with Chinese activities around cables.

CHAKRABARTI: So, Professor Starosielski, then this gets us to the specifics of what Team Telecom, I believe, did around Sea-Me-We 6. Because as Joe described, even the indirect connection to the United States, I understand that the team targets, you know Chinese owned submarines, cables and equipment and then applies the kind of pressure that Joe talked about to get companies to withdraw their involvement from the cable laying. Do I have that right?

STAROSIELSKI: So it's a bit more complex than that. Sea-Me-We 6 is not a Chinese cable, per se. It's a cable that's laid by many companies, that many companies came together to lay. And so there's always pressure being enacted through various companies and the governments in the countries that they're a part of. So this is a global project, incredibly complex project, and they have to choose a supplier to build the cable. So that's a key pressure point in this process.

Is who is going to actually manufacture and lay the cable across the ocean? Not necessarily who's going to own the cable or where the cable is going to land. The question here is which company? And there are only a few companies in the world that lay cable. This is kind of one of those bottleneck kind of pressure points in the global communication system.

So one of those, as Joe mentioned, is SubCom, a U.S. based company. Another is HMN Tech, which is a Chinese company. ... So the question was here, not necessarily should there be Chinese owners of this cable, but should there be a Chinese supplier of the cable? Should there be a manufacturer of the cable that is a Chinese company? And that's where the United States stepped in.

CHAKRABARTI: Okay. And so it stepped in. And what happened then with HMN Tech?

STAROSIELSKI: So what happened is that the consortium had to go with the U.S. based supplier. ... And this is a move that has happened through pressure on previous cable systems before this, both in the Asia Pacific. There is a transatlantic cable example where the Chinese supplier was set to get a contract and then the U.S. put pressure on it.

Everyone worried that you wouldn't be able to sell capacity on that system, that you wouldn't because the U.S. companies wouldn't be allowed to transmit that system because it was made by a Chinese supplier. So the U.S. government put pressure on the system sort of externally and that prompted a change that was a part of a kind of strategic change, but also an economic change because people are worried about this question of capacity and cost and being able to be a viable cable project.

CHAKRABARTI: So then if HMN Tech is not the cable layer for this project, Joe, does that mean that, you know, the concerns that we shared from various members of Congress and ... Washington more generally at the top of the show, are they moot now?

KELLER: I think they're largely addressed by moves like this. I'm not sure that they're moot, though. There were, in fact, reactions to this move, however. So after taking these steps to change the contractor, the supplier, as the court mentioned, the very important part of laying the cable to Chinese stakeholders left the project. And this sort of tit for tat action and reactionary steps. I think these are the types of events that we'll see more often as the U.S. takes specific steps to keep Chinese cables and infrastructure out of the projects that they're involved with, and use whatever methods that they have at their disposal.

CHAKRABARTI: So what was the implication of those Chinese stakeholders in leaving the project?

KELLER: The project obviously went together. They took with them about 20% of the investor capital. But there was a cost in terms of what happened afterwards. You mentioned before this cable, this Europe, Middle East, Asia cable. So this is seemingly in response to the breakdown of a couple of Chinese stakeholders in launching a new project, one in direct competition with the previous cable project that they withdrew themselves from.

And so this is something that seems to mirror this competition. The U.S. is involved with building a cable and then Chinese infrastructure builders forced and compelled to go elsewhere and build infrastructure that seemingly accomplishes the same thing.

CHAKRABSRTI: Okay. I have to say then, given what both of you have said, I'm having difficulty understanding what the actual threat is. What is the threat that Washington is perceiving? Because, you know, as Nicole said earlier, these are really complex systems and that, you know, perhaps maybe the headlines and the quotes are oversimplifying the situation. I mean, we're reading articles where analysts are saying, and you heard one clip at the top of the show that, you know, could China reroute traffic being carried on these particular cables? Or could they, I don't know, engage in some kind of espionage? I mean, Joe, I'd like to hear from you on this. Do you think those threats are legitimate or are they also oversimplified?

KELLER: I think the threats are legitimate. I think the means by which individuals and the U.S. specifically addresses those, it's complicated. So there is fear of espionage, of cyber-attacks, of cable tapping. But there so far have been very few straightforward examples, at least that we know of. Nowadays, there are advanced technological systems that work remotely that use artificial intelligence. These advances in tech can provide some vulnerabilities, however, that have to do with cable security.

There was an instance in 2023, in February, where cables will cut off the coast of Taiwan. Taiwan assumed that China had taken these steps and it really restricted Internet access for a lot of folks. Also, in 2022, Homeland Security thwarted a potential attack to a carrier that has not yet been named in the Pacific Islands servicing Hawaii and Pacific regions. These sorts of activities aren't always privy to us. So it's uncertain exactly what the extent is, but the threat, I feel, is still very much prevalent.

CHAKRABARTI: Okay. Nicole, did you want to respond to that?

STAROSIELSKI: I agree with Joe's assessment of the situation. It's really, there is a threat. But I think that the amount of attention focused on this threat doesn't take into account the complexity of the systems and the actual operations ... of the companies who own them and supply them.

CHAKRABARTI: You know, I'm seeing here regarding specifically the concern about HMN Tech is that the United States, Washington specifically, fears that China's advance into fiber optic cabling, undersea cabling, I've seen the phrase it could be a Trojan horse for military and economic expansion. Because the Chinese government itself has said HMN Tech is a quote, 'model of civil military integration and that the company will offer powerful support for the modernization of our country's national defense.' Joe Keller, how do you read that?

KELLER: I think you've hit the nail on the head. The U.S. really wants to avoid both direct and indirect association with China around telecommunications. They see any connection as an opportunity for Beijing to influence and control that technology against the West, against the U.S.

So this shared cable infrastructure, untrusted Chinese equipment, this could be at a risk of U.S. citizens privacy. It could also be vulnerable to being intercepted by foreign intelligence agencies. So this rerouting, these blocking of cable projects, these are all steps to try to make sure that threat doesn't get closer and closer. And as we mentioned before, I think the threat as well of sanctions for other individuals, the ripple effect of what this does for other countries and companies that are involved in projects, the ripple effect in trying to chill future collaboration at risk of sanctions and other measures that may not be economically viable.

Related Reading

Reuters: "U.S. and China wage war beneath the waves – over internet cables" — "It started out as strictly business: a huge private contract for one of the world’s most advanced undersea fiber-optic cables. It became a trophy in a growing proxy war between the United States and China over technologies that could determine who achieves economic and military dominance for decades to come."

Reuters: "Exclusive: China plans $500 million subsea internet cable to rival US-backed project" — "Chinese state-owned telecom firms are developing a $500 million undersea fiber-optic internet cable network that would link Asia, the Middle East and Europe to rival a similar U.S.-backed project, four people involved in the deal told Reuters."

This program aired on May 22, 2023.

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Stefano Kotsonis Senior Producer, On Point
Stefano Kotsonis is a senior producer for WBUR's On Point.


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Meghna Chakrabarti Host, On Point
Meghna Chakrabarti is the host of On Point.



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