Huh? Are you kidding? Each cable bundle can transmit petabytes of data per second. Think of all the Netflix movies being watched in Japan and Australia transmitted over that cable. Why would anyone encrypt that? Furthermore, the hardware required to encrypt, even if feasible (and that’s unclear), would be astronomical in cost.
Plus, it’s not just about access. A malicious actor could always damage or destroy the cable, cutting off a primary channel of communications.
Plus, it’s not just about access. A malicious actor could always damage or destroy the cable, cutting off a primary channel of communications.