A very basic cypherpunk issue is privacy in communications and data retention. John Gilmore said he wanted “a guarantee — with physics and mathematics, not with laws — that we can give ourselves real privacy of personal communications.”
The secrecy of correspondence or literally translated as secrecy of letters, is a fundamental legal principle enshrined in the constitutions of several European countries.It guarantees that the content of sealed letters is never revealed, and letters in transit are not opened by government officials, or any other third party. It is the main legal basis for the assumption of privacy of correspondence.
The principle has been naturally extended to other forms of communication, including telephony and electronic communications on the Internet, as the constitutional guarantees are generally thought to also cover these forms of communication. However, national telecommunications privacy laws may allow lawful interception, i.e. wiretapping and monitoring of electronic communications in cases of suspicion of crime. Paper letters have, in most jurisdictions, remained outside the legal scope of law enforcement surveillance, even in cases of “reasonable searches and seizures”.
When applied to electronic communication, the principle protects not only the content of the communication, but also the information on when and to whom any messages (if any) have been sent (see: Call detail records), and in the case of mobile communication, the location information of the mobile units. As a consequence, in jurisdictions with a safeguard on secrecy of letters, location data collected from mobile phone networks has a higher level of protection than data collected by vehicle telematics or transport tickets.
Such guarantees require strong cryptography, so cypherpunks are fundamentally opposed to government policies attempting to control the usage or export of cryptography, which remained an issue throughout the late 1990s. The Cypherpunk Manifesto stated “Cypherpunks deplore regulations on cryptography, for encryption is fundamentally a private act.”
This was a central issue for many cypherpunks. Most are passionately opposed to various government attempts to limit cryptography — export laws, promotion of limited key length ciphers, and especially escrowed encryption.