As has already been said, getting national CCW reciprocity accomplished by involving federal legislation and regulation might not bear the fruit some folks would expect.
It even took some repeated efforts and some years before the Drivers License Compact and Non-Resident Violator Compact would eventually become the Driver License Agreement (DLA), and some states reportedly had to be enticed to decide to join.
Then, look at the effort it took to get Congress to finally agree on the training & qualification provisions of the legislation that eventually became LEOSA. If they're going to emphasize currency of training and annual qual standards for active (state of employment) and honorably retired (state of residence) cops, you really think they're going to be any less stringent on private citizens?
Look at the constant changes and shifting of reciprocity among states that already have some degree of agreement, and how it's not hard to find disagreement about training standards. Really think that's going to get easier, rather than harder?
Then, since 3 states (last I recall, but I could be wrong) don't require licenses or permits for concealed carry (but one also offers it), if states somehow miraculously agree tomorrow to honor licenses/permits from all other states, where does that leave residents from states which don't even have licenses or permits? What do they show cops in other states?
The devil is in the details, and this is probably best left to be sorted out by the states, as it involves state permits and records.
I do think that something's eventually going to come out of all of it, though. Probably not something that's going to please everyone.
If they were to treat it like the DLA, it would also mean that certain types of violations by a visitor would be forwarded to the visitor's resident state licensing dept.
Be careful what you wish for, because you might get it, along with all the unanticipated bureaucratic, administrative and variable enforcement details that would follow trying to involve 50 states, territories and a special district.
Be nice to see it in my lifetime, though. LEOSA was a surprising, but overall pleasant, thing to see happen. (Retired cops still have to remember to go through whatever hoops are required to handle the annual qual and get the documentation, though, in addition to keeping their retirement ID current from their respective agencies.) Still a couple things that require some further tweaking, though.
