Encryption without authentication solves a majority of threat vectors that would allow people to look at your private communication. (authentication here means

Encryption without authentication solves a majority of threat vectors that would allow people to look at your private communication. (authentication here means knowing that key K belongs to some organization, not authenticated encryption). If, by default, everything was encrypted, then the internet would be a much better place. Once encryption is in place, it means that active monitoring will be easy to detect because if only a small number of people actually verify that the remote party is who they say they are, then it will still be detected.