According to his originalism, if a weapon can be hand-held, though, it probably still falls under the right o “bear arms”:

WALLACE: What about… a weapon that can fire a hundred shots in a minute?

SCALIA: We’ll see. Obviously the Amendment does not apply to arms that cannot be hand-carried — it’s to keep and “bear,” so it doesn’t apply to cannons — but I suppose here are hand-held rocket launchers that can bring down airplanes, that will have to be decided.

WALLACE: How do you decide that if you’re a textualist?

SCALIA: Very carefully.

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