Read Article I, Section 9, Clause 1.
It is the MIGRATION and Importation Clause... not the Importation Clause.
"All will admit, that, if the word migration were excluded from the clause, it would apply to slaves only. An unsuccessful attempt was made in the Convention to amend this clause by striking out the word migration, and thereby to make it apply to slaves exclusively...
...The conclusion, to my mind, is therefore irresistible, that there are two separate and distinct classes of persons intended to be provided for by this clause.
Although they are both subjects of commerce, the latter class only is the subject of trade and importation. The slaves are not immigrants, and had no exercise of volition in their transportation from Africa to the United States...."
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