Earlier quoted context omitted.
Gun and encryption are two completely different beast. With guns you can execute a crime, with encryption you cannot. It is true that you can plan a crime with the use of encryption, but we don't punish on intentions but only on facts. It is not illegal to plan how to kill someone, while it is illegal to actually kill somebody or to try to do it.
If you use encryption to tell someone to kill, you have executed a crime using encryption.
Anyway we are not going to ban paper, matches, lighters, and the mail services.
You are thinking more like a technician than like a lawyer...