Note 539 — ARTICLE I (continued 3)

Headnotes. Said the Court: "The rule has been asserted with great clearness, that whenever the subjects over which a power to regulate commerce is asserted are in their nature national, or admit of one uniform system or plan of regulation, they may justly be said to be of such a nature as to require exclusive legislation by Congress. Surely transportation of passengers or merchandise through a State, or from one State to another, is of this nature. It is of national importance that over that subject there should be but one regulating power, for if one State can directly tax persons or property passing through it, or tax them indirectly by levying a tax upon their transportation, every other may, and thus commercial intercourse between States remote from each other may be destroyed." 15 Wall. at 279-280, citing Cooley v. Port Wardens, 12 How. 299 (1851); Gilman. v. Philadelphia, 3 Wall. 713 (1866); Crandall v. Nevada, 6 Wall. 35, 42 (1868).