There is another issue brewing, which is going to bring gun licensing into greater focus: nationwide licensing reciprocity. I think people in less-gun-friendly states will fight to have a say in the requirements for licensure of visitors to their states. I can easily imagine calls for national licensure standards.
When Rights become licensed, they are no longer rights, but privileges granted by government - which are then rescinded, taxed or abolished at their whim for whatever reason they deem necessary. It may become very costly and time consuming to go through government red tape for you to exercise a 'right'.
Once citizens are required to be licensed by government in order to exercise an inalienable right, they no longer have rights, but permissions granted by the state. If the right to keep and bear arms requires a license, then in a steady incremental march, speech, press and religion will also end up requiring licensing before one is permitted to engage in those things. This is where history and human nature always go.
I guess if this is where those who want to feel safe and secure need to go - we might as well declare the Constitution null, void and abolished and just stop pretending we have liberty in this land.