Indeed, the nature of email transport is such that security should be somehow enforced while it's not in your domain of total control. It should be presumed all

Indeed, the nature of email transport is such that security should be somehow enforced while it's not in your domain of total control. It should be presumed all sorts of eyes are looking at your package and should be dealt with accordingly. One approach is to write locally, encrypt and send it. Likewise for receiving - receive encrypted and decrypt locally. Thing is how to make this happen to work unobtrusively for users as well as how to make it work with current infrastructure of users not using encryption. That's the challenge. NB: All presuming NSA or whoever doesn't have capability to break your encryption scheme. Great addition would be if attempt of breaking in to your package could notify you, but that's not technically possible as far as I know.