Cardinal Richelieu understood the value of surveillance when he famously said, "If one would give me six lines written by the hand of the most honest man, I would find something in them to have him hanged." Watch someone long enough, and you'll find something to arrest — or just blackmail — with. Privacy is important because without it, surveillance information will be abused: to peep, to sell to marketers and to spy on political enemies — whoever they happen to be at the time.

Cardinal Richelieu understood the value of surveillance when he famously said, "If one would give me six lines written by the hand of the most honest man, I would find something in them to have him hanged." Watch someone long enough, and you'll find something to arrest — or just blackmail — with. Privacy is important because without it, surveillance information will be abused: to peep, to sell to marketers and to spy on political enemies — whoever they happen to be at the time.