Right, and how would that be implemented, in, say, a web browser? Do you really think that the government that&#x27;s forcing all this secret spying would just give up? Or more likely, would they require modifications to the software to leak the key or plaintext?<p>How would users verify that the software was working securely? A webmail provider would need to publish a full client-server API and protocol spec, so that you could run some independent software to audit what was being sent to be sure no leakage was happening. This is simply untenable.<p>Oh and what would really happen is that everyone would lose access to their data since, in general, nobody is able to maintain keys. It&#x27;s pretty understandable that companies have little desire to redesign their whole systems to provide a crappy experience to a nearly non-existent market segment.