Take a couple of minutes to read what was said and really happened not the mediots bs:
No, Donald Trump Doesn’t Want to Register All American Muslims. It’s Just Another Media Smear.
http://www.dailywire.com/news/1269/no-donald-trump-doesnt-want-register-all-american-ben-shapiro
The Federal Government has most all of that information via Census and income tax records. Military used to put your religious preference on the dog tags which is also entered into their permanent military records.