Re: But what about...
The same way he would now.
That could only possibly work for a small subsection of the encryption that goes on, then.
Currently, Alice will encrypt a messge with Bob's ublic key, and he will decrypt it with his private key. For Alice to send the decryption key with the message - she would need Bob's private key. That means it's not private any longer.
You encrypt the stream using a session key
So your system can only possibly work in a mechanism whereby a symmetric session key is negotiated between the endpoints. That cuts out the bulk of such messages. It also means that - were one to want to do something nefarious - it would be trivially easy just to send something other than that session key as the purported decryption key - which would only be discovered much later, when the transmission is decrypted by Law Enforcement. Thus it will be a hindrance to people going about their normal lives, but won't touch anyone who is prepared to fake the session key. And if someone's happy to blow up a building, I doubt there'll be much compunction over lying about a decryption key.
TL;DR: your mechanism is, like so many others, entirely useless when it comes to law enforcement, despite requiring significant intrusion into the private lives of innocent people.
Vic.
Biting the hand that feeds IT
