Interesting how our opponents put the cart before the horse.
How might we private citizens form militias if we are not armed with rifles and ammo of our own? If a governor calls for the militia, but nobody is allowed to be armed, well, that's a bit more like a Wednesday night revival meeting. And if a governor calls the militia, then arms them with weapons from the state's armory, wouldn't that make the militia more of a regular military?
Arms in the hands of private citizens is a prerequisite for there being any such thing as a militia.