Huh? I think you just made this gentleman’s case, or did I misunderstand you?
What will happen is a slow incrementalism intended to leach the firearms out of the most armed citizenry anywhere. It is happening: environmental restrictions against lead ammunition, zoning regulations intended to make possession of firearms in urban and suburban areas impossible, attempts to stretch terrorism laws to cover domestic disarmament. That's what we have to watch for, IMHO.
It sounds like one-hundred to one odds if each weapon had a citizen to handle it. I bet that's better than the odds of slipping on ice. It may not be possible to know how many patrolmen or troopers, if asked to take up arms against their brothers and neighbors, would ditch the powers that be and join the citizenship patrols, but it is not as if there is not a precedence.