Run, do not walk, to read this very interesting comment by Bill Schneier: Wired News: The Eternal Value of Privacy. Here's a taste:
The most common retort against privacy advocates -- by those in favor of ID checks, cameras, databases, data mining and other wholesale surveillance measures -- is this line: "If you aren't doing anything wrong, what do you have to hide?"
Some clever answers: "If I'm not doing anything wrong, then you have no cause to watch me." "Because the government gets to define what's wrong, and they keep changing the definition." "Because you might do something wrong with my information." My problem with quips like these -- as right as they are -- is that they accept the premise that privacy is about hiding a wrong. It's not. Privacy is an inherent human right, and a requirement for maintaining the human condition with dignity and respect.