It’s right to worry about security, but sometimes data trawls can be useful

Should we be afraid of great data trawls surveying us? After the Guardian’s revelations, people have reasons to be uneasy. Nothing is private, everything can be seen by big government surveying emails and phone records or by small-time private detectives slipped a few hundred quid by journalists for scamming and hacking. Tesco knows your tastes and foibles, Oyster and CCTV know where you are and where you’ve been.