The Chinese “display of deep-sea cable-cutting technology” represented a “show of strength,” said Wendy Chang, an analyst at the Mercator Institute for China Studies in Germany, when the technology initially came to light in 2025.

“From continuing to deny its involvement in shadowy operations involving doctored anchors to unveiling equipment to cut fortified cables, China is sending mixed messages about its role in global submarine infrastructure,” said Chang. “It wants to be a player in its construction and operation—but also wants the world to know that it has the capability to disrupt critical infrastructure if necessary.”

China is not alone in having the technological capability to access and potentially cut undersea cables. During the Cold War, the US Navy used a specially modified submarine and divers to secretly tap Soviet naval communications running through an undersea cable in the Sea of Okhotsk. Both the US and Russia continue to operate nuclear submarines and survey ships equipped with robotic submersibles that could access undersea cables. Some of the latest incidents of accidental or suspected sabotage damage to undersea cables have even simply involved ships dragging their anchors across the seafloor.

Dual-use ambiguity raises sabotage concerns

The Chinese researchers have insisted that the cable-cutting technology is intended for civilian purposes involving “marine resource development.” But the South China Morning Post has speculated that the tool could pose a threat to the fiber-optic cables linking to Pacific islands such as Guam, the US overseas territory that hosts several military bases.

Such a tool would also exacerbate Chinese military pressure on the self-governing democracy of Taiwan, which relies on 24 major cables for its global connectivity. Taiwan has faced a series of suspected undersea cable sabotage incidents involving Chinese-owned ships as part of a broader pressure campaign by Chinese military and maritime militia vessels, which have conducted multiple exercises in the waters near Taiwan.

Chinese-flagged cargo ships have even damaged undersea data cables and gas pipelines in the Baltic Sea at least twice in October 2023 and November 2024, affecting European countries such as Germany, Finland, Lithuania, Estonia, and Sweden. Chinese officials described those incidents as accidents.

Given the broader pattern of suspected sabotage incidents, it’s not hard to imagine some cause for concern in the newest cable-cutting tool’s dual-use capabilities. It’s also a reminder of the growing vulnerability of the Internet’s physical backbone, which consists of more than 1.5 million kilometers of submarine cables that stretch across oceans and connect continents.