Phil Zimmermann: Why I Wrote PGP

Why I Wrote PGP (1991, revised 1999)

In this 1991 essay, updated in 1999, Phil Zimmermann explains his motivation for creating PGP: to protect private communication from government surveillance. He argues that email is inherently insecure, compares government surveillance to driftnet fishing, and warns that without strong cryptography, privacy will vanish. He details the Clipper chip and other threats, and calls for widespread encryption to preserve democracy.