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Rh State Commercial Passenger Fishing Vessel Assn., 443 U. S., at 666–667.

It is easy to see the purchase these rules have for reservation-creating treaties like the one at issue in this case. Treaties like that almost invariably designate property as a permanent home for the relevant Tribe. See McGirt v. Oklahoma, 591 U. S. ___, ___ (2020) (slip op., at 5). And the promise of a permanent home necessarily implies certain benefits for the Tribe (and certain responsibilities for the United States). One set of those benefits and responsibilities concerns water. This Court long ago recognized as much in Winters v. United States, 207 U. S. 564 (1908).

That case involved the Milk River, which flows along the northern border of the Fort Belknap Reservation. Id., at 565–567 (statement of McKenna, J.). Upstream landowners invested their own resources to build dams and reservoirs which indirectly deprived the Tribes living on the reservation of water by reducing the volume available downstream. Id., at 567. The United States sued on the Tribes’ behalf to enjoin the landowners’ actions. Id., at 565. In assessing the government’s claim, the Court looked to the agreement establishing that reservation and found no language speaking to the Tribes’ water rights at all. Id., at 575–576. Nevertheless, the Court concluded, the agreement reserved water rights for the Tribes in the Milk River and found for the government. Id., at 577. The Court considered it inconceivable that, having once enjoyed “beneficial use” of nearby waters, the Tribes would have contracted to “give up all th[at].” Id., at 576. After all, the lands described in the reservation “were arid and, without irrigation, were practically valueless,” and “communities could not be established” without access to adequate water. Ibid. (internal quotation marks omitted). For these reasons, the agreement’s provisions designating the land as a permanent home for the Tribes necessarily implied that the Tribes would enjoy continued access to nearby sources of