It doesn’t matter if you have “nothing to hide”. Privacy is a right granted to individuals that underpins the freedoms of expression, association and assembly; all of which are essential for a free, democratic society.
Loss of privacy leads to loss of freedom.
Your freedom of expression is threatened by the surveillance of your internet usage – thought patterns and intentions can be extrapolated from your website visits (rightly or wrongly), and the knowledge that you are being surveilled can make you less likely to research a particular topic. You lose that perspective, and your thought can be pushed in one direction as a result. Similarly, when the things you write online, or communicate privately to others, are surveilled, and you self-censor as a result, the rest of us lose your perspective, and the development of further ideas is stifled.
Arguing that you don’t care about the right to privacy because you have nothing to hide is no different than saying you don’t care about free speech because you have nothing to say.
– Edward Snowden