Article 1, Section 8, Clause 7
St. George Tucker, Blackstone's Commentaries 1:App. 264--651803
7. Congress have power to establish post-offices, and post-roads. And this is one of those cases, in which I have supposed that the states may possess a concurrent, but subordinate authority, to that of the federal government. Concurrent, inasmuch, as there seems to be nothing in the constitution, nor in the nature of the thing itself, which may not be exercised by both, at the same time, without prejudice, or interference; subordinate, because wherever any power is expressly granted to congress, it is to be taken, for granted, that it shall not be contravened by the authority of any particular state. If, therefore, any state should find it necessary to establish post-offices on any road, which is not an established post-road, under the laws of the United States, there seems to be no constitutional objection to its doing so, until congress should think proper to exert its constitutional right to establish a communication by post, between the same places. . . . I put this case merely to shew how far the exercise of these concurrent powers may be reconciled: it is much to be desired that a question of such delicacy may never occur between any state, and the federal government.
The post-office, under proper regulations, is one of the most beneficial establishments which can be introduced by any government; by providing the means of intercourse between the citizens of remote parts of the confederation, on such a regular footing, as must contribute greatly to the convenience of commerce, and to the free, and frequent communication of facts, and sentiments between individuals. Hence the revenue arising from this source will always be more easily collected, and more cheerfully paid, than any other whatever. It appears, that notwithstanding the many unprofitable branches, into which the post-roads have been divided for the convenience of the people of the United States, there still remains a considerable sum that is annually brought into the federal treasury.
It seems reasonable that the product of this branch of the revenue should be, exclusively, applied to the extention of its benefits, until they shall completely pervade every part of the union.
The Founders' Constitution
Volume 3, Article 1, Section 8, Clause 7, Document 5
The University of Chicago Press
Tucker, St. George. Blackstone's Commentaries: With Notes of Reference to the Constitution and Laws of the Federal Government of the United States and of the Commonwealth of Virginia. 5 vols. Philadelphia, 1803. Reprint. South Hackensack, N.J.: Rothman Reprints, 1969.
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