I suppose I will lead with:
The U.S. Constitution does not adequately define "arms". When it was adopted, "arms" included muzzle-loaded muskets and pistols, swords, knives, bows with arrows, and spears. However, a common- law definition would be "light infantry weapons which can be carried and used, together with ammunition, by a single militiaman, functionally equivalent to those commonly used by infantrymen in land warfare." That certainly includes modern rifles and handguns, full-auto machine guns and shotguns, grenade and grenade launchers, flares, smoke, tear gas, incendiary rounds, and anti-tank weapons, but not heavy artillery, rockets, or bombs, or lethal chemical, biological or nuclear weapons. Somewhere in between we need to draw the line. The standard has to be that "arms" includes weapons which would enable citizens to effectively resist government tyranny, but the precise line will be drawn politically rather than constitutionally. The rule should be that "arms" includes all light infantry weapons that do not cause mass destruction. If we follow the rule that personal rights should be interpreted broadly and governmental powers narrowly, which was the intention of the Framers, instead of the reverse, then "arms" must be interpreted broadly.
A legal perspective.
