Commerce Clause. Although it certainly might be overturned by an unfriendly Supreme Court, it's sort of a gray area. A parallel might be drawn to the concealed

Commerce Clause. Although it certainly might be overturned by an unfriendly Supreme Court, it's sort of a gray area. A parallel might be drawn to the concealed carry reciprocity act (https://www.congress.gov/bill/116th-congress/senate-bill/69 https://www.congress.gov/bill/116th-congress/senate-bill/69) currently pending in Congress, in the sense that it would also prevent state and local jurisdictions from enforcing local regulations against individuals who met some Congressional standard (in that case, that they were registered for concealed carry in their place of residence). Constitutional scholars don't have a firm answer for that bill's constitutionality because it's sort of a unique proposed application of Commerce Clause power.