I come next to the right to regulate commerce, the third source from whence the right to make internal improvements is claimed.  It is expressed in the following words:  “Congress shall have power to regulate commerce with foreign nations and among the several States and with the Indian tribes.”  The reasoning applicable to the preceding claims is equally so to this.  The mischief complained of was that this power could not be exercised with advantage by the individual States, and the object was to transfer it to the United States.  The sense in which the power was understood and exercised by the States was doubtless that in which it was transferred to the United States.  The policy was the same as to three branches of this grant, and it is scarcely possible to separate the two first from each other in any view which may be taken of the subject.  The last, relating to the Indian tribes, is of a nature distinct from the others for reasons too well known to require explanation.  Commerce between independent powers or communities is universally regulated by duties and imposts.  It was so regulated by the States before the adoption of this Constitution equally in respect to each other and to foreign powers.  The goods and vessels employed in the trade are the only subjects of regulation.  It can act on none other.  A power, then, to impose such duties and imposts in regard to foreign nations and to prevent any on the trade between the States was the only power granted.

If we recur to the causes which produced the adoption of this Constitution, we shall find that injuries resulting from the regulation of trade by the States respectively and the advantages anticipated from the transfer of the power to Congress were among those which had the most weight.  Instead of acting as a nation in regard to foreign powers, the States individually had commenced a system of restraint on each other whereby the interests of foreign powers were promoted at their expense.  If one State imposed high duties on the goods or vessels of a foreign power to countervail the regulations of such power, the next adjoining States imposed lighter duties to invite those articles into their ports, that they might be transferred thence into the other States, securing the duties to themselves.  This contracted policy in some of the States was soon counteracted by others.  Restraints were immediately laid on such commerce by the suffering States, and thus had grown up a state of affairs disorderly and unnatural, the tendency of which was to destroy the Union itself and with it all hope of realizing those blessings which we had anticipated from the glorious Revolution which had been so recently achieved.  From this deplorable dilemma, or, rather, certain ruin, we were happily rescued by the adoption of the Constitution.