Cybersecurity under the Ocean: Submarine Cables and US National Security

The internet depends on core physical infrastructure to run. Submarine cables are one component of that infrastructure. Over five hundred of these cables, laid across the ocean floor around the world, carry upward of 95 percent of intercontinental internet traffic. Without these cables, the global internet as we know it would not exist.

This paper describes why submarine cables are critical to global internet security and resilience—as well as to economic security, national security, and crisis planning. It also describes some of the key government organizations with stakes in the issue, ranging from the Department of Transportation to interagency committees focused on foreign influence in the United States.