Yes, that's a good point about expecting 'non-surveillance.'

Also, consider how much data they already collect that they're not analyzing properly and/or not acting on. Governments that let people slip before an attack (whether it's due to incompetence or some other reason) shouldn't respond to the attack by asking their law-abiding citizens to give up more privacy. In the U.S. in particular, the post-attack time is often used to push govt. agendas. :/