My father-in-law said exactly that to me. I wanted to reach out and smack him. Unfortunately, it isn't just a "mental copout", either. He is a very intelligent person who has arrived at a conclusion that the government oversight is OK because he has nothing to hide and (I have inferred) he is very afraid of those who do have something to hide.
Ask him if he or someone ever had an issue with someone with power in a company or government. Then ask what does the person have in arsenal when the people with power have a ton of information combined with power?
Although none of us are enamored with North Korea, there was a fair share of atrocities that were committed by UN forces on the NK population and the South Korean government against communist sympathizers in their own country. The Wiki article goes into it in some detail. (No, it doesn't make it OK because "they were doing it".)
(As an aside, I sometimes bitterly contemplate how many great Korean minds were lost in that war because of their personal politics)
War is still war, there were deaths, veterans who weren't the same, etc etc. I'm a child of the 80s, so I can't say I remember the details, but war isn't always a pretty thing. Going by what Wikipedia says (yes, I know it's a single source), the US wasn't exactly smart about how it was handled leading up to the Korean war.
I bet your father-in-law wouldn't take too kindly to Government workers taking a look at his wife naked when they felt like it or recording (if you'll forgive me) their ahem marital moments.
Privacy is a human requirement, as evidenced by the deprivation of privacy as a punishment in prisons, and is much more than protection of those with something to hide.
Privacy seems more like a cultural thing... that doesn't mean that being deprived of it can't be effective as a punishment. In any case, we'd better hope it's a cultural need and not a human need, since it's essentially going away, and I can't think of anything short of the collapse of civilization that could prevent that.
