The treaty as drafted and presented to the Senate provided for an exchange of ratifications at Washington as soon as might be before the 31st day of January, 1903, and should 'go into effect on the tenth day after the exchange of ratifications.' A supplemental convention became necessary, and an exchange of ratifications was provided to be 'as soon as possible and within two months from January 31, 1903.' But subsequent to that date, to wit, March 19, 1903, the Senate added the amendment: 'This convention shall not take effect until the same shall have been approved by the Congress.' Between the treaty, therefore, and the amendment, there was an emphatic difference. The date at which the instrument should go into effect was changed. It cannot be said that the treaty provision related to time and the amendment to sanction merely, and adopted the time of the treaty. To do this would be to interpret the words of the treaty one way and the same words in the amendment another way. We start, then, with the proposition that not the treaty, but the act of Congress, was to fix the date that the treaty should take effect. What date Congress fixed is the question to be considered. It was certainly competent for Congress (with the consent of Cuba) to have given the treaty retrospective, immediate, or prospective operation. Which did Congress do? And in reply we are to remember there is a presumption against retrospective operation, and we have said that words in a statute ought not to have such operation 'unless they are so clear, strong, and imperative that no other meaning can be annexed to them, or unless the intention of the legislature cannot be otherwise satisfied.' United States v. Burr, 159 U.S. 78, 40 L. ed. 82, 15 Sup. Ct. Rep. 1002. On the other hand, it must be admitted that there are words in the act of Congress which, if not of themselves, yet, in connection with events, may be said to look to a retrospective operation. It is not, however, an unusual judicial problem to have to seek the meaning of a law expressed in words not doubtful of themselves, but made so by circumstances or the objects to which they come to be applied.
Both the treaty and the act of Congress concern tariff duties, and 'the usual course in tariff legislation,' we have said, 'has been, inasmuch as some time is necessary to enable importers and business men to act understandingly, to fix a future date at which the statutes are to become operative.' United States v. Burr, supra. And these remarks have application here. The treaty, it may be admitted, was intended as a beneficial concession to Cuba. But conditions in the United States were also to be considered, and we cannot assume that this would have been overlooked by Congress when legislating. It is true, as urged by appellant, that the act of December 17 deals entirely with importations from Cuba, but it is those which would have the most disturbing effect, and on account of which business in like products would have to be accommodated. These, as well as the considerations urged by the appellant, must be kept in mind in seeking the meaning of Congress, and we repeat that, under the Senate amendment, it is the meaning of Congress not the meaning of the convention independent of that of Congress, we are to ascertain. It was open to Cuba to reject the amendment; it was open to Cuba to reject the legislation. If she chose to accept both they became her contracts.