Bruce Schneier argues:
A single national ID is an exceedingly valuable document, and accordingly there’s greater incentive to forge it. There is more security in alert guards paying attention to subtle social cues than bored minimum-wage guards blindly checking IDs.
That’s why, when someone asks me to rate the security of a national ID card on a scale of one to 10, I can’t give an answer. It doesn’t even belong on a scale.
(via David Weinberger)