The bottom line is that despite the suspicions and paranoia expressed by a few, the benefits are much greater.
WW2 was one thing but this is the modern day, societies threats have changed
I think the argument has already been partially presented about this being dangerous (wrong place at wrong time - and even worse now, not having access to a lawyer and trial to prove your innocence if they think your a terrorist), and people are using the "i've got nothing to hide" argument. The problem with this is, "nothing to hide" is wrong - EVERYBODY has got something to hide. Everybody is doing something wrong or illegal somewhere. You think you dont ? Have you downloaded a song off the internet? Ever driven your car too fast above the speed limit, only for a few seconds accidently, or driven while tired? Ever driven home from the pub 2 minutes around the corner *probably* on the edge of 0.05? Walked away from the shop after they put the wrong value in the register? Claimed that home office supply on tax even though you dont use it for work? If a government can criminalize a society, then they have ultimate control because nobody wants to get in trouble with the law.
If your bored and have the time, google the essay "I've got nothing to hide, and other misunderstandings of privacy" by Daniel Solove.
The "suspicious" and "paranoia" of our society should be well respected members - they are the people who have so far lobbied against national ID cards and other invasions of privacy. If you dont want gps units installed in your car monitoring your speed, location and activities [a hypothetical], the "paranoia" are the people who will complain to the press about it.
As for privacy with biometric data - different people have different standards of privacy. At the end of the day, it is not a computer looking at your information (although fishnet data mining is another topic altogether), but another human being. If you are not comfortable with somebody else knowing about your most intimate details, then your privacy has been invaded. All the girls out there with butterfly tatto's near your privates - I bet you did that for your boyfriend, not the 50 year old immigration officer's amusement. If you dont understand this - what level of privacy would you tolerate another person knowing information about you? Would you be comfortable with biometric data such as fingerprints or iris? How about security cameras watching everywhere you go? How about somebody at telstra seeing which porn sites you are looking up on the internet? How about cameras in your own home watching you have sex? Why do you have curtains in your living room and bedroom. After all - your not doing anything wrong, so what have you got to hide?