As a sovereign, Arizona has the inherent power to exclude persons from its territory, subject only to those limitations expressed in the Constitution or constitution- ally imposed by Congress. That power to exclude has long been recognized as inherent in sovereignty. Emer de Vattel's seminal 1758 treatise on the Law of Nations stated:
"The sovereign may forbid the entrance of his territory either to foreigners in general, or in particular cases, or to certain persons, or for certain particular pur- poses, according as he may think it advantageous to the state. There is nothing in all this, that does not flow from the rights of domain and sovereignty: every one is obliged to pay respect to the prohibition; and whoever dares violate it, incurs the penalty decreed to render it effectual."
There is no doubt that "before the adoption of the constitution of the United States" each State had the author- ity to "prevent [itself] from being burdened by an influx of persons." Mayor of New York v. Miln, 11 Pet. 102, 132-133 (1837). And the Constitution did not strip the States of that authority. To the contrary, two of the Constitution's provisions were designed to enable the States to prevent "the intrusion of obnoxious aliens through other States."
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Nor can federal power over illegal immigration be deemed exclusive because of what the Court's opinion solicitously calls "foreign countries[ '] concern[s] about the status, safety, and security of their nationals in the United States," ante, at 3. The Constitution gives all those on our shores the protections of the Bill of Rights--but just as those rights are not expanded for foreign nationals because of their countries' views (some countries, for example, have recently discovered the death penalty to be barbaric), neither are the fundamental sovereign powers of the States abridged to accommodate foreign countries' views. Even in its international relations, the Federal Government must live with the inconvenient fact that it is a Union of independent States, who have their own sovereign powers. This is not the first time it has found that a nuisance and a bother in the conduct of foreign policy. Four years ago, for example, the Government importuned us to interfere with thoroughly constitutional state judicial procedures in the criminal trial of foreign nationals because the international community, and even an opinion of the International Court of Justice, disapproved them. See Medellín v. Texas, 552 U. S. 491 (2008) . We rejected that request, as we should reject the Executive's invocation of foreign-affairs considerations here. Though it may upset foreign powers--and even when the Federal Government desperately wants to avoid upsetting foreign powers--the States have the right to protect their borders against foreign nationals, just as they have the right to execute foreign nationals for murder.
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The President said at a news conference that the new program is "the right thing to do" in light of Congress's failure to pass the Administration's proposed revision of the Immigration Act. 7 Perhaps it is, though Arizona may not think so. But to say, as the Court does, that Arizona contradicts federal law by enforcing applications of the Immigration Act that the President declines to enforce boggles the mind.
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Are the sovereign States at the mercy of the Federal Executive's refusal to enforce the Nation's immigration laws?
A good way of answering that question is to ask: Would the States conceivably have entered into the Union if the Constitution itself contained the Court's holding? Today's judgment surely fails that test. At the Constitutional Convention of 1787, the delegates contended with "the jealousy of the states with regard to their sovereignty." 1 Records of the Federal Convention 19 (M. Farrand ed. 1911) (statement of Edmund Randolph). Through ratification of the fundamental charter that the Convention produced, the States ceded much of their sovereignty to the Federal Government. But much of it remained jealously guarded--as reflected in the innumerable proposals that never left Independence Hall. Now, imagine a provision--perhaps inserted right after Art. I, §8, cl. 4, the Naturalization Clause--which included among the enumerated powers of Congress "To establish Limitations upon Immigration that will be exclusive and that will be enforced only to the extent the President deems appropriate." The delegates to the Grand Convention would have rushed to the exits.
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Arizona has moved to protect its sovereignty--not in contradiction of federal law, but in complete compliance with it. The laws under challenge here do not extend or revise federal immigration restrictions, but merely enforce those restrictions more effectively. If securing its territory in this fashion is not within the power of Arizona, we should cease referring to it as a sovereign State. I dissent.