This is obviously an extreme example, but it's valid nonetheless. nazi germany had to build the database (thanks IBM) they needed, a future nazi, fascists or the like government wouldn't have to, those databases already exists in much more details nazi germany would have dreamed of (facebook seems to know you're gay before you do or your family does [1]).
But this nazi example is one everybody can relate to because we're all familiar with it. But if this is too strong we could go a bit further in history and talked about richelieu "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." and the current state of us law [2].
Well the reasoning is quite simple actually, if you care for freedom then you should care for privacy. Without privacy there's no freedom possible.
Maybe read some of the many posts around about privacy and freedom and rebuttal of the "I don't do anything wrong so I don't have to hide" argument:
you could start with the schneier's blog: https://www.schneier.com/blog/archives/2006/05/the_value_of_...
But let me try to make a point of why you should personally care even though you don't know or understand why. This is a case of closing the barn door after the horse is gone, if you later learn the hard way you should have cared and go the extra step of protecting your data, you couldn't go back and get your data back.
And the sad reality is that if you have to learn this way, it means that history has indeed repeated itself again and you're enjoying living under a tyranny.
But this nazi example is one everybody can relate to because we're all familiar with it. But if this is too strong we could go a bit further in history and talked about richelieu "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." and the current state of us law [2].
[1]: http://americablog.com/2013/03/facebook-might-know-youre-gay... [2]: http://www.harveysilverglate.com/Books/ThreeFeloniesaDay.asp...