Quantum computing will eventually break the public-key cryptography that secures global communications, financial systems, and national security infrastructure today. The United States government has chosen post-quantum cryptography (PQC), new mathematical algorithms, as its primary response to this new threat, with federal agencies mandated to complete migration by 2035. A 2020 advisory by the National Security Agency (NSA) advisory declined to approve quantum key distribution (QKD), a hardware-based alternative whose security rests on the laws of physics rather than mathematical assumptions, citing five technical limitations. This report assesses the current state of the transition of quantum cryptography and the evolving role of QKD in the U.S. landscape.