Re: The Halting Problem

The revelation here (for me, anyway) is that if arbitrary crypto were made illegal, the burden of proof would be on the prosecution which would have to crack the message (at least partially).

I believe the burden would actually be on them to crack the message entirely. Otherwise, you are applying arbitrary algorithms to what may be a random stream. If you get something comprehensible out, you have either partially cracked the message, or run into the British Museum problem (AKA 100 monkeys with typewriters).