This paper presents a U.S.-focused design and evaluation of CRYSTALS-Kyber-based encryption protocols tailored for secure satellite-to-ground communications. With the emerging threat posed by quantum computing to traditional public-key cryptography, the integration of post-quantum encryption schemes such as Kyber has become critical for safeguarding space-based assets. The study evaluates the Kyber protocol in simulated orbital conditions, measuring handshake efficiency, encrypted throughput, packet retransmission resilience, CPU and memory consumption, session recovery latency, and scalability. Kyber demonstrated superior performance in reconnection speed, loss recovery, and session scalability compared to RSA and ECC baselines, while maintaining acceptable computational loads for deployment on both ground stations and small satellite platforms. The protocol’s resilience to variable latency and degraded signal environments confirms its suitability for low-Earth orbit (LEO) communication profiles. Results support phased deployment in U.S. aerospace networks, beginning with mission-critical command links. This work contributes new empirical insights into the readiness of post-quantum cryptography for real-world space applications.