In 1992 the U.S. State Department told a Berkeley math student that his encryption code was a weapon.
Not a figure of speech. A letter, dated August 20, 1992, from the Office of Defense Trade Controls: Daniel Bernstein's algorithm was "designated as a defense article under U.S. Munitions List Category XIII(b)(1)." The same list as bombs. Using it at home was legal. Posting it where a foreigner could read it was arms trafficking, and the State Department told him not to bother applying for a licence, because the code was too secure to approve.
He sued in 1995. In April 1996 a federal judge ruled that source code is speech. In 1999 the appeals court agreed, and the export rules came down.
Every bitcoin key you hold is protected by the class of math that Washington classified as a munition within living memory. It didn't become legal to share because the government changed its mind. It became legal because one graduate student refused to register as an arms dealer.
The next time someone tells you self-custody is paranoid, remember that the official position, not long ago, was that the tools for it should not be allowed to leave the country.




