Page:Joseph Story, Commentaries on the Constitution of the United States (1st ed, 1833, vol III).djvu/11

 CH. XVI.] § 1099. It follows, from the very nature of the power, that to be useful, it must be exclusive; for concurrent power in the states would bring back all the evils and embarrassments, which the uniform rule of the constitution was designed to remedy. And, accordingly, though there was a momentary hesitation, when the constitution first went into operation, whether the power might not still be exercised by the states, subject only to the control of congress, so far as the legislation of the latter extended, as the supreme law; yet the power is now firmly established to be exclusive. The Federalist, indeed, introduced this very case, as entirely clear, to illustrate the doctrine of an exclusive power by implication, arising from the repugnancy of a similar power in the states. "This power must necessarily be exclusive," say the authors; "because, if each state had power to prescribe a distinct rule, there could be no uniform rule."