I wonder if he feels the same about envelopes and the post office.
An envelope prevents the contents from being read after all.
Presumably, everybody should send all post without one.
That would include bank statements, personal finance, private information -- exactly the same things that are only slowly becoming protected on the internet.
Email is still today the equivalent of a post-card not a letter, and will remain so until end-to-end encryption is in-place.
Would *you* have *your* bank send *your* statement on a post-card Mr Blunkett?