Generally speaking, according to rules of international law, one State is not concerned with, and, therefore, not required to be cognizant of, the constitutional law of another State with which it has dealings. With respect, however, to the constitutional treaty-making powers of the governmental organs of that State, other States are required to be informed; - qui cum alio cuutralnt, est, eel debet esse non ignarus conditionis ejus - and, therefore, it is no great ground of complaint on the part of a State, as, for example, England, in whose Executive is exclusively vested the treaty-making power, when a treaty project which has been mutually agreed upon between the Executive of that country and the Executive of the United States, fails of approval, or is amended in the Senate.20

It would seem, however, that when the American Senate amends a treaty, and then formally ratifies it as amended, and returns it to the President for him to submit to the other nation concerned, there is some ground for complaint that thereby such nation is improperly placed in a position where it is called upon to pass upon a project which has not been based upon negotiations between the two States in which opportunity has been given to state and argue the merits upon both sides of the project. In other words, that the onus of accepting or rejecting a completed project is thereby improperly placed upon the treaty-making organ of the foreign State. This would appear to have been the objection made by Lord Lansdowne in his note of February 22, 190l, to Lord Pauncefote, with reference to the Hay-Pauncefote treaty which in December, 1900, had been amended and then approved by the Senate. This treaty, it will be remembered, had for its aim the definite determination of certain matters which had been covered by the Clayton-Bulwer treaty, the subsisting force of which had been in dispute. The Senate's amendment to the new arrangement agreed upon between Secretary of State Hay and Lord Lansdowne, was amended by the Senate by the insertion of the statement that the Clayton-Bulwer treaty was "hereby superseded." Referring to this provision, Lord Lansdowne said: "The Clayton-Bulwer treaty is an international contract of unquestioned validity; a contract, which, according to well-established international usage, ought not to be abrogated or modified save with the consent of both, the parties to the contract. His Majesty's Government find themselves confronted with a proposal communicated to them by the United States Government, without any previous attempt to ascertain their views, for the abrogation of the Clayton-Bulwer treaty."

20 In order, however, to avoid the possibility of a misunderstanding and consequent irritation, it lias been a common, though not uniform, practice to state explicitly in the powers granted those who are to negotiate a treaty, that their action, in order to become binding on the United States, requires the approval of the President and the Senate.