This is going to be one of those posts where I shake the ant farm a bit, because I think this is one cases where the prejudices of the left and right will conspire to make a ridiculous mess out of something that should really be quite simple. But people being the way people are, I accept that this is a subject of great complexity, so let me play devil’s advocate for a bit.
I tend to think the right to bear arms, being fundamental, applies to all people, but with a federal judiciary that wants to drag the whole “INTERMEDIATE SCRUTINY MEANS A WEAK RIGHT TO BEAR ARMS!” meme forward, this is a less damaging opinion on the subject than I could have imagined.
If the right’s “central component,†as interpreted by Heller, 554 U.S. at 599, is to secure an individual’s ability to defend his home, business, or family (which often includes children who are American citizens), why exactly should all aliens who are not lawfully resident be left to the mercies of burglars and assailants? That must be at least one reason behind the wave of challenges to § 922(g)(5). But courts must defer to Congress as it lawfully exercises its constitutional power to distinguish between citizens and non-citizens, or between lawful and unlawful aliens, and to ensure safety and order.
Why must the courts defer to Congress? What special insights does Congress have as to the constitutionality of laws? As offensive  as it may be to conservative populism, I’ve never been able to reconcile the idea of fundamental rights with the idea of rights of citizenship as it currently stands. For instance, this quote from the opinion, citing precedent in the 1950 case of Johnson v. Eisentrager:
The alien, to whom the United States has been traditionally hospitable, has been accorded a generous and ascending scale of rights as he increases his identity with our society. Mere lawful presence in the country creates an implied assurance of safe conduct and gives him certain rights; they become more extensive and secure when he makes preliminary declaration of intention to become a citizen, and they expand to those of full citizenship upon naturalization.
I think this is only true, because as a society, we’ve had a poor concept of rights. If a right is fundamental, then it is fundamental; it’s exercise cannot be infringed by any dictate of Congress, or the Executive, or the states (by the 14th Amendment). If a right is a citizenship right, rather than a natural one, such as voting, then it is not a true, inviolable natural right, but one exercised by a citizen, subject to the laws regarding citizenry.
I think whether the right to keep and bear arms is a right of citizenship, or a fundamental natural right is a debate worth having. But to a large degree, the courts have already declared it a fundamental one. I happen to believe that is correct, and it should have consequences, conservative populism railing against illegal immigration, or liberal dogma railing against gun right be damned. One of those consequences is that all individuals have a right self-preservation, and thus a right to the tools necessary to protect those ends.
I think if you want to ban firearms possession, mere possession, from illegal aliens, the government should have to prove, beyond a reasonable doubt, two things; that the possession was in furtherance of an unlawful act (e.g. that the illegal immigrant was here robbing banks, dealing drugs, etc) and that he did indeed possess the weapon in furtherance of those acts. That’s a far cry from, say, conducting an immigration raid of a business in a shitty neighborhood, and finding a pistol in the personal possession of one of the of the unlawful immigrants who was busted. I have no issues with prosecuting people who are here illegally and deporting them, but a fundamental right is a fundamental right, and the idea that the right to keep and bear arms is a fundamental right has consequences. One of those is that is a right of all people, regardless of citizenship or immigration status. If you want to prosecute someone for gun possession, then you need to prove their possession was in furtherance of an unlawful end, and not merely possessed for lawful self-protection.