Second Amendment, Illegal Aliens, and Noncitizens More Generally:

U.S. v. Guerrero-Leco, 2008 WL 4534226 (W.D.N.C. Oct. 6, 2008), holds that the Second Amendment doesn't apply to illegal aliens. The court correctly declines to follow pre-Heller Fourth Circuit precedent that upheld the ban on illegal aliens' possession of guns, and instead reasons itself from Heller. The reasoning, unfortunately, isn't very detailed:

The Supreme Court did not find that all individuals present in America are protected by the Second Amendment. Rather, the Court described that protection as belonging to American citizens [footnote] who "inherited [it] from our English ancestors." Nothing in the opinion purports to extend the Second Amendment's protection to those outside the American political community like the defendant who allegedly entered and remained unlawfully in the country. This inferior court will not read into Heller a more expansive right than recognized therein.

[Footnote:] Examples include: "we do not read the Second Amendment to protect the right of citizens to carry arms for any sort of confrontation," Id. at 2799 (emphasis in original); "this right was intended ... and was guaranteed to, and to be exercised and enjoyed by the citizen," Id. at 2806 (quoting Andrews v. State, 50 Tenn. 165, 183 (1871)(ellipsis in original; internal quotation marks omitted)); "the Second Amendment does not protect those weapons not typically possessed by law-abiding citizens for lawful purposes," Id. at 2815-16; "[The District's requirement] makes it impossible for citizens to use [firearms in the home] for the core lawful purpose of self-defense and is hence unconstitutional," Id. at 2818.

But I doubt that the Court's casual references to citizens were a deliberate judgment that the right only applies to citizens (and thus not to, for instance, legally resident aliens), or should be treated as holding or even strong dictum on the matter. "Citizen" is sometimes loosely used, including in court opinions, to generally mean individuals; and more broadly courts may talk about the rights of citizens (who are the bulk of rightsholders) without foreclosing the possibility that noncitizens might have such rights as well. Consider, for instance, the full context for the first passage quoted in the footnote: "Thus, we do not read the Second Amendment to protect the right of citizens to carry arms for any sort of confrontation, just as we do not read the First Amendment to protect the right of citizens to speak for any purpose." The Court wasn't suggesting that the First Amendment protects only citizens (a view that the Court has generally expressly rejected); it was using citizens to mean something broader (or at least saying that citizens have the right without denying that noncitizens might as well).

There are good and careful arguments that can be made in favor of the conclusion that the Second Amendment doesn't apply to illegal aliens -- such as those put forth by a magistrate judge in the Southern District of Florida in August -- but I don't think that the court's argument here is by itself persuasive.