Read up on the Clipper chip: A chip which sort of being promoted to be the "official" way to do crypto in the US. Specifically designed to be decryptable by the NSA via "key escrow".

https://en.wikipedia.org/wiki/Clipper_chip

It died when Matt Blaze figured out a way to trick the clipper chip doing encryption that the NSA could NOT decrypt.

Just do a search for Phil Zimmermann and what they did to him in the 90's for having the audacity to create PGP.

http://www.loundy.com/Roadside_T-Shirt.html is one example, there are probably others. It ended up going in a sane direction, but it's a bit crazy to imagine in hindsight.

Many developers that worked on crypto would cross the border into Canada to meet up and work on crypto to get around the export restrictions (crypto software was classified as a weapon; exporting it could get you the same punishment as exporting a missile).

Read "Crypto: how the code rebels beat the government, saving privacy in the digital age" by Steven Levy. He outlines the whole story of public crypto until about 2000. Good read, too.