In order, therefore, that the end of the Constitution may be accomplished, that it may really be the supreme law of the land, it must have provided a way in which its only true meaning may be ascertained and definitively settled. Unless it has provided a final interpreter of its meaning, it is the merest folly to style it the supreme law of the land, or to call on us to obey its requirement. Is the Constitution thus deficient? Does it demand uniformity, and at the same time deny the use of those means which are absolutely necessary to produce such uniformity? Does it present a variable, ever-changing standard of duty, and yet demand complete uniformity in practice? There are three departments in the Government, namely, the Executive, the Legislative, and the Judicial. The first two of these are each, to some extent, supreme in its own sphere; and its acts are incapable of revision elsewhere. "Thus, in measures exclusively of a political, legislative, or executive character, it is plain, that, as the supreme authority as to these questions belongs to the legislative and executive departments, they cannot be re-examined elsewhere. Thus, Congress having the power to declare war, to levy taxes, to appropriate money, to regulate intercourse and commerce with foreign nations, their mode of executing these powers can never become the subject of re-examination in any other tribunal. So, the power to make treaties being confided to the President and Senate, when a treaty is properly ratified, it becomes the law of the land, and no other tribunal can gainsay its stipulations. Yet cases may readily be imagined, in which a tax may be laid, or a treaty made, upon motions and grounds wholly beside the intention of the Constitution. The remedy, however, in such cases is solely by an appeal to the people at the elections, or by the salutary power of amendment provided by the Constitution itself.