No the federal Government can not regulate the possession of a machine-gun because that is purely a local matter. Joe use the machine gun for his own and never took any part in interstate commerce. According to Wickard v. Filburn Congress can regulate purely intrastate activity that is not itself “commercial,” in that is is not for sale but its for own use.
1. Is it a defense that Joe’s possession of the machine-gun was insignificant in the grand scheme of things? After all, he is just one person who possesses only one firearm. Yes Joe allow defend his possession of the machine