Post-quantum cryptography and the quantum future of cybersecurity

While public key cryptography enables the Internet to carry secure communications for billions of people every day, this critical technology is not infallible. It is well known that the Internet needs to transition to new ``post-quantum'' cryptosystems, to protect against the possibility of future cryptanalysis using quantum computers. This Perspective suggests that there is a broader scope for using quantum technologies to enhance cybersecurity, including fundamentally different approaches to constructing hardware security modules, to protect the secret keys that are the linchpin of cryptography on the Internet.