The United States Submarine Cable Security Policy Act of 2026 establishes a comprehensive framework for regulating underwater fiber-optic cables that carry international communications and data to and from the United States. Within 180 days of enactment, the Federal Communications Commission must develop and adopt a national submarine cable security policy with two tiers of requirements: standard security measures for most cables and enhanced measures for cables posing heightened national security risks. The bill streamlines the licensing process by allowing applicants to self-certify ownership structures and security compliance, with FCC decisions required within 45 days (or one year if undergoing security review), and automatic approval if the FCC misses these deadlines. Existing cable operators can opt into the new security framework, and qualified applicants may begin landing cables before final license approval unless a security review committee objects within 20 days. The legislation affects submarine cable operators and providers seeking to connect U.S. infrastructure to foreign nations, particularly those involving equipment from untrusted vendors or cables to countries identified as posing security concerns.