How about on practical grounds? Is the federal government really gonna tell DC and the state of Maryland, where most of them live, they must allow people who have, say, a Washington state CCW, where no training whatsoever is required, to carry concealed in their territory? It'll never happen. The "CCW reciprocity law" is going to be several hundred pages. It's going to require "lowest common denominator" rules for states issuing CCWs. Public safety funds will be cut off for states who don't comply. It won't take long before the feds are in control of all CCW issuance rules. Again, if you don't believe that, you've been living on a different planet. If you wanted to undo a quarter century of phenomenal state progress in the realm of CCW within a couple of years, getting the feds involved is the way to do it.