Public Key Cryptography (PKC) dramatically lowers the risk of information intercept and also lowers the risk of impersonation. PKC vastly increases security. For example, Google allows people to send queries to them encrypted. But they cannot decrypt the queries sent by others with what they give you, only Google can. Besides encrypting and decrypting, public keys can authenticate that a person is who they claim to be.
Patent fights can often obscure inventors. National security concerns intensify this problem. Inventors, in this case, worked in secret.
Significantly, Ellis, Cocks, and Williamson suggest they invented public-key cryptography about 1972, working for the British government. However, the technology was classified as secret by the British and the US National Security Agency (NSA) until 1997.
Eventually, not knowing about the classified innovation, Diffie and Hellman to “discovered” PKC in 1976. Particularly, Diffie and Hellman invented public-key encryption, maybe working for a telecom, maybe for Sun, and possibly for a government agency; it isn’t clear.
Ronald Rivest, Adi Shamir, and Leonard Adleman made a successor system, RSA, that commercialized public key encryption. Public key encryption is what allows “secure” transmission of data over the Internet, among other things.