I don't need a national ID to prove I'm a citizen. I have both a birth certificate and a passport. My wife has the former. Last I checked, a birth certificate was issued by states.
Well make sure you carry them around with you at all times
Because that case will end up in the courts .. it's either everyone shows prove of ID or no one does
If you pick on one group of people .. it will called discrimination and the courts will throw the law out