Overview of China’s Undersea Cable Strategy
News and Analysis:
A recent congressional report indicates that the Chinese government is actively developing technologies aimed at severing undersea communications cables as part of its extensive military expansion and preparations for potential conflict.
The U.S.-China Economic and Security Review Commission’s report highlights that China is employing new cable-cutting technologies as part of its strategy for “gray zone” warfare—operations that occur below the threshold of direct military engagement.
The report states, “China has increasingly engaged in undersea cable-cutting activities as a gray zone pressure tactic, and there is mounting evidence that Beijing is developing new cable-cutting technologies for potential wartime use.” Researchers affiliated with the People’s Liberation Army are reportedly investigating methods to efficiently sever deep-sea cables, with numerous patents filed for such technologies.
Undersea cables form the backbone of global communication networks, carrying approximately 95% of international internet traffic. These cables are crucial for financial transactions, governmental operations, commercial activities, and military communications.
The report notes that in February, scientists from the China Ship Scientific Research Center unveiled a design for an “electric cutting device for deep-sea cables,” capable of cutting through armored cables at depths exceeding 13,000 feet. This technology raises concerns about potential disruptions to communications around Taiwan during a military invasion.
The document reveals instances where Chinese vessels have sabotaged critical undersea cables both near Taiwan and in the Baltic Sea. For example, two incidents involving Chinese-owned ships occurred near Taiwan since early 2025, where they cut cables while exhibiting unusual movement patterns. Additionally, a Chinese vessel was implicated in severing two undersea cables in the Baltic Sea in November 2024.
The report also warns that China could exploit its cable repair ships to conduct espionage against the United States and its allies. There have been allegations that China obstructed Vietnam’s efforts to repair damaged undersea cables amid ongoing territorial disputes over the Paracel Islands.
The findings underscore China’s commitment to enhancing its capabilities to target global communication infrastructure during future conflicts—posing significant risks to connectivity among U.S. allies during crises. The House Homeland subcommittee on transportation and maritime security plans to hold a hearing on these foreign threats soon.
