First, it's abundantly clear that the national government is already in possession of massive amounts of information about us as individuals. The whole "The One World Order Government will know what color my eyes are" conspiracy arguments are pretty obsolete at this point.
Second, more and more of our society is based around confirming state ID, from a national basis (getting on an airplane) to a local one (securing the right to vote, not to mention buy alcohol or cash a check).
So, fine. Let's just do it, and then then focus our attention on all the problems that come with such a national ID, including ensuring that everyone can get one, making them as counterfeit-proof as possible, and dealing with errors in the databases. Those problems all happen now, but they're obscured by being split out among the 50 states, and allow said states to play games with them (re voting rights). Let's tackle them as-is and move on.
Reshared post from +Gizmodo
An important read for your favorite conspiracy theorist:
No, Real ID Is Not a National ID Card
Big Brother! Little Brother! Medium-sized Brother! Conspiracy-minded websites are ramping up the rhetoric in the lead-up to full enforcement of the Real ID Act, set to happen early next year. “It’s a National ID card!” they scream. No, no it’s not.