Ash, I have said this repeatedly, the junior is NOT to blame. You must have missed the key story in this affair: NO PROCEDURES WERE BROKEN, despite officials initially stating otherwise (tha's also why they have stopped mentioning "breach of procedures" afterwards).
Yes, that's right, the Junior did NOTHING wrong.
The problem came from two issues:
(1) originally, internal gov post *was* secure, but then they outsourced it (i.e. degraded the containment) without adjusting the risk model accordingly;
(2) unlike the US there is no overall UK gov encryption standard, as far as I can tell that's because of a mix of political reasons and the desire of the MI services to snoop on anything that moves (which is, incidentally, very helpful if said service is repeatedly breached by spies, but I digress). Crypto is normally only handed out on request ('sponsored'), there isn't a default application.
Not only did the junior follow procedure (he used internal gov post, which is not supposed to be the same as a public letterbox), but if he had been actually required to encrypt the material he would not have the tools to do so.
Who is to blame? Well, who takes care of Gov security? Who should have spotted this increase in transport risk? Strange, isn't it, that we haven't heard a peep from the likes of CESG? They have been *very*, *very* quiet throughout this whole affair, despite proclaiming themselves to be the "National Technical Authority for Information Assurance" (I'm quoting their website here).
Nah, it's easier to blame some junior. His superior has already been given a new and cushy job in Cabinet Office (so much for "resigning" then) so the only thing left now is to pray every night that none of this data will be abused.
Everyone involved is secretely hoping the CDs have simply landed in a crack in a van somewhere so that it will eventually go quiet again, because the first report of abuse will REALLY make this story come back. And at that moment the danger is no longer theoretical.
BTW, it's actually easy to counter the resulting risk, just the volume makes it a larger task. But, as I expected, the Gov has chosen a method that only furthers their own goals without going near addressing the present risks. I won't help them this time - let them stew for a bit.