Whitfield Diffie is, in essence, a cryptohipster. Or, one might call him a cryptotarian (crypto libertarian). He graduated from MIT, and studied cryptography just for the thrill of it. In the early 70's, Diffie had the foresight to realize that one day, people would have their own computers. He believed that "if people then used their computers to exchange emails, they deserved the right to encrypt their messages in order to guarantee their privacy."
I do agree that private citizens have a right to have access to secure encryption technologies. Encryption technologies would be used to protect communication - the same communication that might take place face-to-face. Since in-person private conversation has never been a right that's been questioned, why should we give up our communication rights if it's simply a different medium of communication? Living in America, we have a right to privacy. This right shouldn't be infringed upon due to the development of the internet. If someone is able to develop their own encryption system, they should be able to use it at their will. There's a lot of work that goes into developing/utilizing such a system, including the logistical problems that come with key distribution. If people want to go through the trouble of exchanging keys, they should be able to communicate in private.