Today, once people understand that "assault weapons" are firearms that are cosmetically threatening but functionally indistinguishable from other long guns, they are willing to accord these arms a place within the right to keep and bear arms. Machine guns, in contrast, really are functionally different. Machine guns are rarely used in crime; and lawfully possessed machine guns, which must be registered with the federal government, are essentially absent from the world of gun crime. Nevertheless, even many people who consider themselves strong Second Amendment supporters cannot bear the thought of a constitutional right to own machine guns.
Attorney Stephen Halbrook, suggests that, "artillery pieces, tanks, nuclear devices and other heavy ordinances are not constitutionally protected" arms, nor are "grenades, bombs, bazookas and other devices … which have never been commonly possessed for self-defense." (Steven Halbrook, What the Framers Intended: A Linguistic Interpretation of the Second Amendment, 49 L. & CONTEMP. PROB. at 153 (1986).)
But the Halbrook test sidesteps the fact that militia uses, not just personal-defense uses, are part of the core of the Second Amendment. Moreover, the Halbrook test could allow governments to ban new types of guns or weapons, since those weapons, being new, "have never been commonly possessed for self-defense." The test could allow Second Amendment technology to be frozen, as if the government claimed that new communications devices are unprotected by the First Amendment because they have never (heretofore) been commonly used for speech.
Just as the civilized-warfare test protects firearms that many persons want excluded from the Second Amendment, the test also excludes firearms that many persons want to be included. The civilized-warfare cases protected large handguns, but in some applications excluded small, highly concealable handguns. This would suggest that modern bans on small, inexpensive handguns might not violate the Second Amendment. On the other hand, small handguns such as the Colt .25 pistol were used by the United States military during the Second World War. (See Charles W. Pate, "Researching the Martial .25 Colt Pistol," Man at Arms, Jan./Feb. 1995, 20-29.) (Of course, anyone using the civilized-warfare test to make such an argument must also accept the flip side of the civilized-warfare coin: "Assault weapon" prohibition is plainly unconstitutional.)
The nineteenth-century minority theory, however, would recognize small, relatively inexpensive handguns as highly suitable for personal defense, and accord them Second Amendment protection regardless of their militia utility. Twentieth-century constitutional law reflects a special concern for problems of minorities and the poor that was not present in nineteenth-century law. Since a small handgun may be the only effective means of protection that is affordable to a poor person, and since the poor and minorities tend to receive inferior police protection, modern equal-protection analysis might find some problems with banning inexpensive guns, even if one sets aside the Second Amendment. (Note, Markus T. Funk, The Melting Point Case-in-Point, 85 J. CRIM. L. & CRIMINOL. 764 (1995).)