It's always been a question of practicality more than morality when it comes to the mass confiscation of firearms. They'd happily confiscate every firearm they could from the population, but they just don't have the resources to pull that off. That's why the emphasis has been on bans that dry up supply and piece meal confiscation. In fact, the folks here pretend that gun confiscation isn't happening on a daily basis, but it is throughout the country in courts. Judges order people charged with crimes to surrender their weapons or otherwise dispose of them as conditions of their bond. Judges order those convicted of felonies or domestic violence to surrender their firearms or otherwise dispose of them. It doesn't matter if the crime is non-violent police when executing arrest warrants will confiscate firearms every time and whether the person ends up guilty or not forfeiture is always a problem when it comes to firearms (anything to get them off the street). The government drives people into poverty through socialism and then does government programs to buy firearms from them. US population is about 5% of the total world's population, but we have 25% of the world's prison population. A huge segment of society cannot legally own firearms now and every year the offenses that bar ownership of them increase in number.
The government's grip is as tight as it can be right now, but they're always working to make it tighter. Would they use a disaster of national proportions to do so? I think it would still be an issue of practicality, but bans would increase and piece meal confiscation would increase substantially. The first opportunity the powers that be get they'll happily burn the Constitution and turn us into a system of mob rule, because they know through history they can always manipulate a mob.