10th amendment gives the states the rights to all other powers not granted to the government.
I know its been tossed aside by the necessary and proper clause, but that still hasnt stopped states from making their own laws, own state IDs, etc.
it also doesnt stop states from suing the federal government (states vs obamacare)
we dont need redundancy in the system.
state IDs work perfectly fine, we dont need the fed govt having more information on the citizens than it already has.
it would also most likely be required for everyone to carry/have, which would be illegal unless it was entirely free program, which means more tax payers money, which the fed govt doesnt have
lastly, im pretty sure the tea party and the rest of america are telling the government they want less government in their lives (recent elections had a sweep of republicans being voted in)