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14 this Court has long consulted original and historical understandings of the Constitution’s structure and the principles of “sovereignty and comity” it embraces. BMW of North America, Inc. v. Gore, 517 U. S. 559, 572 (1996). This Court has invoked as well a number of the Constitution’s express provisions—including “the Due Process Clause and the Full Faith and Credit Clause.” Phillips Petroleum Co. v. Shutts, 472 U. S. 797, 818 (1985). The antidiscrimination principle found in our dormant Commerce Clause cases may well represent one more effort to mediate competing claims of sovereign authority under our horizontal separation of powers. But none of this means, as petitioners suppose, that any question about the ability of a State to project its power extraterritorially must yield to an “almost per se” rule under the dormant Commerce Clause. This Court has never before claimed so much “ground for judicial supremacy under the banner of the dormant Commerce Clause.” United Haulers Assn., Inc. v. Oneida-Herkimer Solid Waste Management Authority, 550 U. S. 330, 347 (2007). We see no reason to change course now.