In short, the non-proprietary feature of the standards, maintained by volunteer groups of engineers under the mantle of The InternetSociety, is what accounts for their phenomenal trajectory and velocity over the last fifteen years.
But according to John Palfrey, executive director of the Berkman Center for Internet and Society at Harvard Law School, complying with government censoring efforts is a "wildly expensive thing" for Internet firms to do.
Today Zimmermann is a fellow at the Stanford Law School Center For Internet and Society, and focuses on Zfone, an encryption scheme for VoIP phone calls.