Congress shall have power to regulate commerce with foreign nations,
  and among the several States, and with the Indian tribes.

That to “regulate commerce” does not mean to make a road, or dig a canal, or clear out a river, or deepen a harbor would seem to be obvious to the common understanding.  To “regulate” admits or affirms the preexistence of the thing to be regulated.  In this case it presupposes the existence of commerce, and, of course, the means by which and the channels through which commerce is carried on.  It confers no creative power; it only assumes control over that which may have been brought into existence through other agencies, such as State legislation and the industry and enterprise of individuals.  If the definition of the word “regulate” is to include the provision of means to carry on commerce, then have Congress not only power to deepen harbors, clear out rivers, dig canals, and make roads, but also to build ships, railroad cars, and other vehicles, all of which are necessary to commerce.  There is no middle ground.  If the power to regulate can be legitimately construed into a power to create or facilitate, then not only the bays and harbors, but the roads and canals and all the means of transporting merchandise among the several States, are put at the disposition of Congress.  This power to regulate commerce was construed and exercised immediately after the adoption of the Constitution, and has been exercised to the present day, by prescribing general rules by which commerce should be conducted.  With foreign nations it has been regulated by treaties defining the rights of citizens and subjects, as well as by acts of Congress imposing duties and restrictions embracing vessels, seamen, cargoes, and passengers.  It has been regulated among the States by acts of Congress relating to the coasting trade and the vessels employed therein, and for the better security of passengers in vessels propelled by steam, and by the removal of all restrictions upon internal trade.  It has been regulated, with the Indian tribes by our intercourse laws, prescribing the manner in which it shall be carried on.  Thus each branch of this grant of power was exercised soon after the adoption of the Constitution, and has continued to be exercised to the present day.  If a more extended construction be adopted, it is impossible for the human mind to fix on a limit to the exercise of the power other than the will and discretion of Congress.  It sweeps into the vortex of national power and jurisdiction not only harbors and inlets, rivers and little streams, but canals, turnpikes, and railroads—­every species of improvement which can facilitate or create trade and intercourse “with foreign nations, and among the several States, and with the Indian tribes.”