Okay, but those were slaves. I would love to see Attorney General Holder make the argument that these restrictions on the importation of slaves weren’t immigration laws, because slaves were more like commodities, and therefore this precedent doesn’t apply. (But I’m sure that he would make it with a straight face.)
We have a somewhat later law that is closer to the situation that Arizona (and every other state) finds itself in today with respect to illegal immigration. In 1824, New York state had become rather tired of poor immigrants arriving by ship and becoming public charges on New York City’s charities. They passed a law requiring that ship captains post a bond “not to exceed $300, for every passenger, to indemnify and save harmless the mayor, &c., of the city of New York, and the overseers of the poor of the city, from all expenses of the maintenance of such person, or of the child or children of such person, born after such importation; in case such person, child or children, shall become chargeable to the city within two years.” (And many other Atlantic Ocean states did likewise.)
Does this sound familiar? Arizona’s argument for this law is that illegal immigrants are a strain on a variety of public services. That was New York’s argument in 1824 as well. But note that New York was not simply enforcing federal immigration law. It was imposing an additional set of requirements beyond federal law. The defendant in that case actually made much the same argument as opponents of the Arizona law: “that this was a regulation of commerce, and that the power to regulate commerce was exclusively vested in congress. Hence this law, passed by a state, was unconstitutional.”
Yet when the U.S. Supreme Court decided this case in New York v. Miln (1837), the Court concluded that unless Congress was explicitly given exclusive authority, or the states were prohibited from exercising that power, states were free to exercise that power as well.
The states passed and enforced laws against slave importation before 1808, when federal law still allowed it — with no apparent legal challenge. This demonstrates pretty persuasively that state authority to regulate immigration was concurrent with federal authority. Even if Arizona’s new law were stricter than federal law, there would be a persuasive case that the state law would be constitutional — like New York’s law upheld in Miln. But Arizona’s law is not stricter; it is only enforcing federal law.
If the history of state laws regulating immigration from outside of the U.S. and how the U.S. Supreme Court dealt with them is any indication, U.S. v. Arizona is going to be a slam dunk.