The reasons for restraining the power to prevent migration hither for twenty years, were, to the best of my recollection, these: That, as at this time, we had immense and almost immeasurable territory, peopled by not more than two millions and a half of inhabitants, it was of very great consequence to encourage the emigration of able, skilful, and industrious Europeans. The wise conduct of William Penn, and the unexampled growth of Pennsylvania, were cited. It was said, that the portals of the only temple of true freedom now existing on earth should be thrown open to all mankind; that all foreigners of industrious habits should be welcome, and none more so than men of science, and such as may bring to us arts we are unacquainted with, or the means of perfecting those in which we are not yet sufficiently skilled—capitalists whose wealth may add to our commerce or domestic improvements; let the door be ever and most affectionately open to illustrious exiles and sufferers in the cause of liberty; in short, open it liberally to science, to merit, and talents, wherever found, and receive and make them your own. That the safest mode would be to pursue the course for twenty years, and not, before that period, put it at all into the power of Congress to shut it; that, by that time, the Union would be so settled, and our population would be so much increased, we could proceed on our own stock, without the farther accession of foreigners; that, as Congress were to be prohibited from stopping the importation of slaves to settle the Southern States, as no obstacle was to be thrown in the way of their increase and settlement for that period, let it be so with the Northern and Eastern, to which, particularly New York and Philadelphia, it was expected most of the emigrants would go from Europe: and it so happened, for, previous to the year 1808, more than double as many Europeans emigrated to these States, as of Africans were imported into the Southern States.
… I will only mention here, as it is perfectly within my recollection, that the power was given to Congress to regulate the commerce by water between the States, and it being feared, by the Southern, that the Eastern would, whenever they could, do so to the disadvantage of the Southern States, you will find, in the 6th section of the 1st article, Congress are prevented from taxing exports, or giving preference to the ports of one State over another, or obliging vessels bound from one State to clear, enter, or pay duties in another; which restrictions, more clearly than any thing else, prove what the power to regulate commerce among the several States means.
