n of the Court. tion of the laws and, in t, deprives it of its propw, particularly in that the inding and conclusive upon laration that appellee's prodele of food injurious to the pubnstitutes a fraud on the public." egulate commerce is the power "to which commerce is to be governed," 9 Wheat. 1, 196, and extends to the ments in such commerce. Reid v. Col137; Lottery Case, 188 U. S. 321; United are & Hudson Co., 213 U. S. 366; Hope v. 227 U. S. 308; Clark Distilling Co. v. Westd R. Co., 242 U. S. 311; United States v. Hill, 20; McCormick & Co. v. Brown, 286 U. S. 131. r "is complete in itself, may be exercised to its extent and acknowledges no limitations other than escribed by the Constitution." Gibbons v. Ogden, 1, 196. Hence Congress is free to exclude from interte commerce articles whose use in the states for which ey are destined it may reasonably conceive to be injurious to the public health, morals or welfare, Reid v. Colorado, supra; Lottery Case, supra; Hipolite Egg Co. v. United States, 220 U. S. 45; Hope v. United States, supra, or which contravene the policy of the state of their destination. Kentucky Whip & Collar Co. v. Illinois Central R. Co., 299 U. S. 334. Such regulation is not a forbidden invasion of state power either because its motive or its consequence is to restrict the use of articles of commerce within the states of destination, and is not prohibited unless by the due process clause of the Fifth Amendment. And it is no objection to the exertion of the power to regulate interstate commerce that its exercise is attended by the same incidents which attend the exercise of the police power of the states. Seven Cases v. United States, 239 U. S. 510, 514; Hamilt Kentucky Opinion of the Court. 304 U.S. own courts are concerned, be taken as notice to the state which they represented. The Government argues that recognition of the Soviet Government, an action which for many purposes validated here that government's previous acts within its own territory, see Underhill v. Hernandez, 168 U. S. 250; Oetjen v. Central Leather Co., 246 U. S. 297; Ricaud v. American Metal Co., 246 U. S. 304; United States v. Belmont, 301 U. S. 324; Dougherty v. Equitable Life Assurance Society, 266 N. Y. 71, 84, 85; 193 N. E. 897; Luther v. Sagor & Co., [1921] 3 K. B. D. 532, operates to set at naught all the legal consequences of the prior recognition by the United States of the Provisional Government and its representatives, as though such recognition had never been accorded. This is tantamount to saying that the judgments in suits maintained here by the diplomatic representatives of the Provisional Government, valid when rendered, became invalid upon recognition of the Soviet Government. The argument thus ignores the distinction between the effect of our recognition of a foreign government with respect to its acts within its own territory prior to recognition, and the effect upon previous transactions consummated here between its predecessor and our own nationals. The one operates only to validate to a limited extent acts of a de facto government which by virtue of the recognition, has become a government de jure. But it does not follow that recognition renders of no effect transactions here with a prior recognized government in conformity to the declared policy of our own Government. The very purpose of the recognition by our Government is that our nationals may be conclusively advised with what government they may safely carry on business transactions and who its representatives are. If those transactions, valid when entered into, were to be disregarded after the later recognition of a successor government, recognition would be but an idle ceremony, yielding none of the advantages of established diplomatic relations in enabling business transactions to proceed, and affording no protection to our own nationals in carrying them on. So far as we are advised no court has sanctioned such a doctrine. The notion that the judgment in suits maintained by the representative of the Provisional Government would not be conclusive upon all successor governments, was considered and rejected in Russian Government v. Lehigh Valley R. Co., supra. An application for writ of prohibition was denied by this Court. 265 U. S. 573. We conclude that the recognition of the Soviet Government left unaffected those legal consequences of the previous recognition of the Provisional Government and its representatives, which attached to action taken here prior to the later recognition. Third. If the claim of the Russian Government was barred by limitation the United States as its assignee can be in no better position either because of the rule nullum tempus or by virtue of the terms of the assignment. We need waste no time on refinements upon the suggested distinction between rights and remedies, for we may assume for present purposes that the United States acquired by the assignment whatever rights then survived the running of the statute against the Russian Government, and that it may assert those rights subject to such plea of limitations as may be made by petitioner. As has already been noted, the rule nullum tempus rests on the public policy of protecting the domestic sovereign. from omissions of its own officers and agents whose neglect, through lapse of time, would otherwise deprive it of rights. But the circumstances of the present case admit of no appeal to such a policy. There has been no neglect or delay by the United States or its agents, and it has lost no rights by any lapse of time after the assignment. The question is whether the exemption of the United States from the consequences of the neglect of its own agents is enough to relieve it from the consequences of the Russian Government's failure to prosecute the claim. Proof, under a plea of limitation, that the six-year statutory period had run before the assignment offends against no policy of protecting the domestic sovereign. It deprives the United States of no right, for the proof demonstrates that the United States never acquired a right free of a preexisting infirmity, the running of limitations against its assignor, which public policy does not forbid. United States v. Buford, 3 Pet. 12, 30; King v. Morrall, 6 Price 24, 28, 30. Assuming that the respective rights of petitioner and the Soviet Government could have been altered and that petitioner's right to plead the statute of limitations curtailed by force of an executive agreement between the President and the Soviet Government, we can find nothing in the agreement and assignment of November 16, 1933, which purports to enlarge the assigned rights in the hands of the United States, or to free it from the consequences of the failure of the Russian Government to prosecute its claim within the statutory period. The agreement and assignment are embodied in a letter of Mr. Litvinov, People's Commissar of Foreign Affairs of the Soviet Government, to the President and the President's letter of the same date in reply. So far as now relevant the document signed in behalf of the Soviet Government makes mention of "amounts admitted to be due or that may be found to be due it as the successor of prior governments or otherwise from American nationals, including corporations, companies, partnerships or associations." It purports to "release and assign all such amounts to the Government of the United States" and the Soviet Government agrees, preparatory to final settlement of claims between it and the United States and the claims of their nationals, "not to make any claims with 126 Opinion of the Court. respect to (b) Acts done or settlements made by or with the Government of the United States, or public officials of the United States, or its nationals, relating to property, credits, or obligations of any Government of Russia or nationals thereof." The relevant portion of the document signed by the President is expressed in the following paragraph: "I am glad to have these undertakings by your Government and I shall be pleased to notify your Government in each case of any amount realized by the Government of the United States from the release and assignment to it of the amounts admitted to be due, or that may be found to be due." There is nothing in either document to suggest that the United States was to acquire or exert any greater rights than its transferor or that the President by mere executive action purported or intended to alter or diminish the rights of the debtor with respect to any assigned claims, or that the United States, as assignee, is to do more than the Soviet Government could have done after diplomatic recognition—that is, collect the claims in conformity to local law. Even the language of a treaty wherever reasonably possible will be construed so as not to override state laws or to impair rights arising under them. United States v. Arredondo, 6 Pet. 691, 748; Haver v. Yaker, 9 Wall. 32, 34; Dooley v. United States, 182 U. S. 222, 230; Nielsen v. Johnson, 279 U. S. 47, 52; Todok v. Union State Bank, 281 U. S. 449, 454. The assignment left unaffected the right of petitioner to set up against the United States the previous running of the statute of limitations. Fourth. Respondent assails the finding of the district court that there was an unqualified repudiation by petitioner of its liability on the account, and in support of its contention presents an elaborate review of the evidence. The evidence is said to establish that petitioner's |