434 U.S. 452 (98 S.Ct. 799, 54 L.Ed.2d 682)
UNITED STATES STEEL CORPORATION et al., Appellants, v. MULTISTATE TAX COMMISSION et al.
No. 76-635.
Argued: Oct. 11, 1977.
Decided: Feb. 21, 1978.
Mr. Justice POWELL delivered the opinion of the Court.
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Article I, § 10, cl. 1, of the Constitution—the Treaty Clause declares: "No State shall enter into Any Treaty, Alliance or Confederation . . . ." Yet Art. I, § 10, cl. 3—the Compact Clause—permits the States to enter into "agreements" or "compacts," so long as congressional consent is obtained. The Framers clearly perceived compacts and agreements as differing from treaties. 10 The records of the Constitutional Convention, however, are barren of any clue as to the precise contours of the agreements and compacts governed by the Compact Clause. 11 This suggests that the Framers used the words "treaty," "compact," and "agreement" as terms of art, for which no explanation was required 12 and with which we are unfamiliar. Further evidence that the Framers ascribed precise meanings to these words appears in contemporary commentary. 13
Whatever distinct meanings the Framers attributed to the terms in Art. I, § 10, those meanings were soon lost. In 1833, Mr. Justice Story perceived no clear distinction among any of the terms. 14 Lacking any clue as to the categorical definitions the Framers had ascribed to them, Mr. Justice Story developed his own theory. Treaties, alliances, and confederations, he wrote, genera ly connote military and political accords and are forbidden to the States. Compacts and agreements, on the other hand, embrace "mere private rights of sovereignty; such as questions of boundary; interests in land situate in the territory of each other; and other internal regulations for the mutual comfort and convenience of States bordering on each other." 2 J. Story, Commentaries on the Constitution of the United States § 1403, p. 264 (T. Cooley ed. 1873). In the latter situations, congressional consent was required, Story felt, "in order to check any infringement of the rights of the national government." Ibid.
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12
Some commentators have theorized that the Framers understood those terms in relation to the precisely defined categories, fashionable in the contemporary literature of international law, of accords between sovereigns. See, e. g., Engdahl, Characterization of Interstate Arrangements: When Is a Compact Not a Compact?, 64 Mich.L.Rev. 63 (1965); Weinfeld, What Did the Framers of the Federal Constitution Mean by "Agreements or Compacts"?, 3 U.Chi.L.Rev. 453 (1936). The international jurist most widely cited in the first 50 years after the Revolution was Emmerich de Vattel. 1 J. Kent, Commentaries on American Law 18 (1826). In 1775, Benjamin Franklin acknowledged receipt of three copies of a new edition, in French, of Vattel's Law of Nations and remarked that the book "has been continually in the hands of the members of our Congress now sitting . . . ." 2 F. Wharton, United States Revolutionary Diplomatic Correspondence 64 (1889), cited in Weinfeld, supra, at 458.
Vattel differentiated between "treaties," which were made either for perpetuity or for a considerable period, and "agreements, conventions, and pactions," which "are perfected in their execution once for all." E. Vattel, Law of Nations 192 (J. Chitty ed. 1883). Unlike a "treaty" or "alliance," an "agreement" or "paction" was perfected upon execution:
"[T]hose compacts, which are accomplished once for all, and not by successive acts,—are no sooner executed then they are completed and perfected. If they are valid, they have in their own nature a perpetual and irrevocable effect . . . ." Id., at 208.
This distinction between supposedly ongoing accords, such as military alliances, and instantaneously executed, though perpetually effective agreements, such as boundary settlements, may have informed the drafting in Art. I, § 10. The Framers clearly recognized the necessity for amicable resolution of boundary disputes and related grievances. See Virginia v. West Virginia, 246 U.S. 565, 597-600, 38 S.Ct. 400, 404-405, 59 L.Ed. 1272 (1918); Frankfurter & Landis, The Compact Clause of the Constitution—A Study in Interstate Adjustments, 34 Yale L.J. 685, 692-695 (1925). Interstate agreements were a method with which they were familiar. Id., at 694, 732-734. Although these dispositive compacts affected the interests of the States involved, they did not represent the continuing threat to the other States embodied in a "treaty of alliance," to use Vattel's words. E. Vattel, supra, at 192.
13
St. George Tucker, who along with Madison and Edmund Randolph was a Virginia commissioner to the Annapolis Convention of 1786, drew a distinction between "treaties, alliances, and confederations" on the one hand, and "agreements or compacts" on the other:
"The former relate ordinarily to subjects of great national magnitude and importance, and are often perpetual, or made for a considerable period of time; the power of making these is altogether prohibited to the individual states; but agreements, or compacts, concerning transitory or local affairs, or such as cannot possibly affect any other interest but that of the parties, may still be entered into by the respective states, with the consent of congress." 1 W. Blackstone, Commentaries, Appendix 310 (S. Tucker ed. 1803) (footnotes omitted).
Tucker cited Vattel as authority for his interpretation of Art. I, § 10.