I think the problem isn't that the ideas/reasons for privacy aren't being communicated. It's that a lot of people are seriously worried they will be a victim of a terrorist attack (and the government tells them this invasion of privacy will protect them from that) and when they hear the other side's arguments they are happy to fall back on the 'I've got nothing to hide' argument. Honestly it's a nice mindset to be in so I understand why it's hard to convince them otherwise.