" We also recognize another important limitation on the right to keep and carry arms. Miller said, as we have explained, that the sorts of weapons protected were those “in common use at the time.” 307 U. S., at 179. We think that limitation is fairly supported by the historical tradition of prohibiting the carrying of “dangerous and unusual weapons.” See 4 Blackstone 148–149 (1769); 3 B. Wilson, Works of the Honourable James Wilson 79 (1804); J. Dunlap, The New-York Justice 8 (1815); C. Humphreys, A Compendium of the Common Law in Force in Kentucky 482 (1822); 1 W. Russell, A Treatise on Crimes and Indictable Misdemeanors 271–272 (1831); H. Stephen, Summary of the Criminal Law 48 (1840); E. Lewis, An Abridgment of the Criminal Law of the United States 64 (1847); F. Wharton, A Treatise on the Criminal Law of the United States 726 (1852). See alsoStatev.Langford, 10 N. C. 381, 383–384 (1824);O’Neillv.State, 16Ala. 65, 67 (1849);Englishv.State, 35Tex. 473, 476 (1871);Statev.Lanier, 71 N. C. 288, 289 (1874).
It may be objected that if weapons that are most useful in military service—M-16 rifles and the like—may be banned, then theSecond Amendmentright is completely detached from the prefatory clause. But as we have said, the conception of the militia at the time of theSecond Amendment’s ratification was the body of all citizens capable of military service, who would bring the sorts of lawful weapons that they possessed at home to militia duty. It may well be true today that a militia, to be as effective as militias in the 18th century, would require sophisticated arms that are highly unusual in society at large. Indeed, it may be true that no amount of small arms could be useful against modern-day bombers and tanks. But the fact that modern developments have limited the degree of fit between the prefatory clause and the protected right cannot change our interpretation of the right.
However, the only reason that M16's are relatively rare is that they have been restricted/taxed/semi-outlawed since their origin. Thus, that sounds like a self-fulfilling prophecy.