Report warns of undersea cable threats

A new report commissioned by the United States Congress warns that Beijing could secretly cut undersea cables linking the United States to Asia, stressing the need to protect these vital infrastructures. These cables carry most of the world’s internet traffic and are crucial for global communications.

Most cuts are accidental

The report explains that most undersea cable cuts are unintentional, caused by things like ship anchors dragging across the seafloor, fishing nets, and underwater landslides. However, recent events in the Baltic Sea and near Taiwan, involving Russian or Chinese vessels, have sparked concerns about deliberate sabotage.

U.S. commission assesses China’s capabilities

The U.S.-China Economic and Security Review Commission (USCC), which advises Congress, ordered the report to evaluate China’s ability to disrupt undersea cables. It concludes that China is seeking to dominate deep-sea areas and is using undersea cables as a "gray zone" weapon—meaning it can exert influence without direct military conflict.

China’s advanced underwater tools

The report details China’s development of dual-use technologies, including a submersible named Striver that can dive to 10,000 meters, swarms of interconnected underwater drones, and "hibernating" cable-cutting devices that could be activated later. These tools allow for covert operations that are hard to trace.

Cables are hard to attack and hard to blame

Undersea cables are attractive targets because attacks on them are quiet, hard to trace, and unlikely to lead to direct conflict. This aligns with the "gray zone" strategy, which seeks to gain strategic advantages without openly using military force. Some cables, especially those linking the U.S. to Taiwan, Japan, and the Philippines, are more vulnerable because they pass through shallow, busy waters claimed by Beijing.

Some cables are more exposed

The report includes a vulnerability index that ranks trans-Pacific cables based on how exposed they are. Ten of the most at-risk cables include Google’s TPU, Meta’s ORCA, and E2A, which is jointly owned by Verizon and companies from Japan, South Korea, and Taiwan. Disrupting these cables could severely impact communication between the U.S. and Asia.

Disruption would have wide effects

Cutting a single cable could overwhelm the direct data links between the U.S. and its Asian allies, forcing data to take longer and slower routes. If multiple cables were cut during a crisis, such as one involving Taiwan, the entire trans-Pacific communication capacity could be disrupted, with data having to travel around the globe.

Report urges stronger defenses

The report recommends that the U.S. improve surveillance with allies, using shared maritime tracking tools, more patrols, and stricter sanctions. It also calls for rebuilding aging repair fleets, prepositioning equipment, and investing heavily in both civilian and military underwater capabilities to match China’s progress in this area since 2014.