Every law-abiding American citizen already has a license to carry a concealed weapon: it's called the 2nd Amendment. It's nice to see some state governments obeying that law. Maybe one day they all will, though Nebraska will be on the tail end of any such movement.
I'm guessing that if citizens in these states want to have an additional license so they can exercise their right in states that don't obey the law, they could find a way to get an out of state permit. Or maybe their state could offer some kind of permit protocol they could go through if they wanted a license for other states.