The strategic rivalry between the United States and China has shifted from land and air to the ocean floor, where undersea cables now serve as the primary infrastructure for 95% to 99% of global internet traffic. According to ThinkChina and recent reports from Reuters, this competition for “data highways” is evolving from a commercial market battle into a high-stakes struggle for digital sovereignty, security standards, and control over global financial transactions worth over US$10 trillion daily.
Why is the undersea cable market a new geopolitical frontier?
Undersea cables are no longer just commercial assets; they are now critical infrastructure where national security and geopolitics intersect. According to Su Tzu-yun, director at the Institute for National Defense and Security Research, the market is increasingly defined by bloc-based rivalry. While the US focuses on security screenings and leveraging alliances to exclude Chinese firms, China utilizes its Digital Silk Road initiative to provide low-cost, end-to-end solutions to nations across the Global South. The shift is evident in project rerouting, such as the SeaMeWe-6 cable, which saw contracts move from Chinese suppliers to US-based SubCom following intense lobbying.
The undersea cable hardware market is projected to grow from roughly US$20 billion in 2026 to US$55 billion by 2034, driven largely by the massive data demands of artificial intelligence.
How are US and Chinese companies competing for market share?
The global undersea cable market has historically been dominated by a small group of Western and Japanese firms, but Chinese participation has grown significantly. Ding Gang of the Chongyang Institute for Financial Studies notes that four countries—the US, Japan, France, and China—control nearly 90% of the market. US firms currently hold over 30% of the share, while China’s HMN Tech has captured approximately 15% and continues to expand. Despite US sanctions on Huawei in 2019, which led to the divestment and rebranding of its submarine cable division, HMN Tech has successfully undertaken 140 projects across 70 countries, according to a 2025 report from the China Academy of Information and Communications Technology.
What are the risks of a “split” internet?
While geopolitical tensions rise, experts argue that the internet remains a physically integrated global entity. Wang Yiwei, director of the Institute of International Affairs at Renmin University of China, maintains that splitting the internet into opposing blocs is technically difficult due to the interconnected nature of global infrastructure. However, trust is declining. Following the Edward Snowden revelations regarding the PRISM surveillance program, many nations have sought to bypass US-centric infrastructure, viewing it as a potential vector for data collection. This desire for digital independence has fueled the growth of non-Western infrastructure projects.
How are nations preparing for undersea infrastructure conflicts?
The protection of cables has become a major concern as undersea lines are increasingly viewed as targets in “grey-zone” conflicts. Recent incidents in the Baltic Sea, the North Sea, and near the Taiwan Strait have highlighted the vulnerability of these assets. According to reports from the Shangri-La Dialogue, 17 nations have issued “Guiding Principles for Underwater Infrastructure Defence Exchanges.” Notably, both the US and China declined to participate in this framework. Instead, the US, UK, and Australia have turned to the AUKUS partnership to develop uncrewed undersea vehicle technology, a move widely interpreted by analysts as a strategic effort to counter Chinese naval and intelligence operations.
Frequently Asked Questions
Are undersea cables easily damaged?
Yes. Cable breaks are common due to anchor drags or natural events, but recent geopolitical tensions have raised concerns about intentional sabotage in the event of a crisis.
Can a country “turn off” the internet for another?
Because the internet is a decentralized network of networks, it is difficult to shut down entirely, though countries can restrict access at landing stations or through domestic firewall policies.
Why is the US restricting Chinese cable companies?
Citing national security and data privacy, the US Federal Communications Commission has begun tightening licensing requirements to ensure that sensitive communications infrastructure remains under the control of “trusted” technology partners.
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