If passed, this law would not -- I repeat, WOULD NOT
-- involve the Feds in any state's carry permit system. ALL this law would do is require each state to recognize carry licenses/permits issued by any other state. That's something that should already be happening under the provisions of Article 4, Section 1 of the Constitution:
"Full Faith and Credit shall be given in each State to the public Acts, Records, and judicial Proceedings of every other State. And the Congress may by general Laws prescribe the Manner in which such Acts, Records and Proceedings shall be proved, and the Effect thereof."
A marriage license is no more and no less a public act or record than a carry license. So why do all states recognize marriage licenses from other states (and other countries), but not carry licenses?