On the Reddit forums there is a subreddit called /r/changemyview where people post their (often controversial) views and want to hear arguments from others about why their views should be changed.
One of the rest posts was by a user who felt that "I believe the government should be allowed to view my e-mails, tap my phone calls, and view my web history for national security concerns."
The reply by user 161719 describes the process by which surveillance becomes a tool for total oppression and control of a population. He talks about his actual experiences in his home country and how surveillance is used against the populous.
A directly link to the reply is here, it is well worth the read: http://web.archive.org/web/20130611184727/www.reddit.com/r/changemyview/comments/1fv4r6/i_believe_the_government_should_be_allowed_to/caeb3pl