In March testimony before the U.S.-China Economic and Security Review Commission, former Taiwanese legislator and Hudson Institute senior fellow Jason Hsu highlighted a critical vulnerability that rarely makes headlines: the undersea fiber-optic cables carrying 95% of the world’s data. These slender, fragile lines—linking everything from financial trades to daily messages—are largely unprotected from natural disasters or deliberate sabotage by hostile actors.
Taiwan relies on 24 such cables, landing at just eight stations. Hsu warned that severing three key clusters near the Bashi Channel would cut off nearly all of the island’s digital bandwidth instantly. The economic toll would hit an estimated $55 million per day, not counting the ripple effects on the global semiconductor supply chain. Taiwan lacks its own dedicated cable-repair vessel, and the international repair fleet takes an average of 40 days to fix a single break.
Since 2023, vessels flagged under convenience—but crewed by Chinese nationals—have repeatedly dragged anchors across cables linking Taiwan to its outer islands like Penghu and Kinmen, causing slower internet and communication outages. These acts are part of Beijing’s gray-zone warfare, designed to undermine Taiwanese sovereignty while staying below the threshold of open conflict to avoid clear attribution.
The Baltic Sea has become a parallel testing ground, with suspected Russian shadow-fleet vessels damaging the EstLink2 power cable and the C-Lion1 data line between Finland and Germany. Northern Europe and East Asia now face the same shadow war, waged by adversaries learning from each other’s tactics.
Legislative Response: The Strategic Subsea Cables Act
Hsu urged Congress to pass the Strategic Subsea Cables Act, introduced by Sens. John Barrasso (R-Wyo.) and Jeanne Shaheen (D-N.H.). The Senate Foreign Relations Committee approved it unanimously in January, and it has since been folded into the fiscal year 2027 National Defense Authorization Act as a bipartisan amendment. The bill requires the president to impose blocking sanctions and revoke visas for foreign persons and vessels behind undersea sabotage, while also targeting insurers, flag registries, port operators, and ship captains enabling the shadow fleet. It creates a single interagency committee to coordinate among a dozen federal offices and commits the U.S. to leading allies in hardening infrastructure and speeding repairs.
Critics note that attributing sabotage is difficult—some incidents may stem from crew negligence. Hsu countered that intelligence is key to identifying saboteurs and building a case for sanctions and visa revocations. “The bill builds both the evidence base and deterrence against bad actors seeking to harm international communications,” he said.
Urgency and Global Stakes
Time is running short. China has launched new vessels purpose-built for seabed operations, likely for cable sabotage. Each month of delay keeps the cost of cutting a cable near zero. Hsu emphasized that U.S. credibility with allies across the Indo-Pacific and Europe hinges on matching rhetoric with action. Japan, the Philippines, Australia, and Baltic states share the same vulnerabilities.
“The next cable cut is coming; the only question is whether the U.S. will make them pay a price for it,” Hsu wrote. The Senate has already shown bipartisan support, but final passage—whether as a standalone bill or through the defense spending measure—remains critical.
For context, recent debates on election security have also highlighted infrastructure vulnerabilities, as seen in Sen. Warner’s criticism of Trump’s approach. Meanwhile, ongoing tensions in the Strait of Hormuz, where Energy Secretary Wright vowed to keep shipping lanes open, underscore the broader challenge of protecting critical chokepoints. The undersea cable threat is a test of whether free societies can defend the infrastructure that sustains modern life.
