In the famous case of _Gibbons_ v. _Ogden_ (1824), the Supreme Court gave an interpretation of the commerce clause of the Constitution which also had a profound effect upon subsequent history. In the course of its decision the court declared unconstitutional a law of the State of New York which had granted an exclusive right to operate steamboats in the waters of New York. The regulation of commerce, the court held, had been given exclusively to Congress, and "commerce" as used in the Constitution comprehended not merely traffic and intercourse but also navigation. The power to regulate was regarded as a unit. In regulating commerce with foreign nations, the power of Congress does not stop at the jurisdictional lines of the several States. "If a foreign voyage may commence or terminate at a port within a State, then the power of Congress may be exercised within a State." Similarly, the court reasoned that commerce "among the States" cannot stop at the external boundary of each State. "Commerce among the States must of necessity be commerce with the States." In short, while expressly disclaiming that Congress had the power to regulate the internal commerce of a State, the court asserted the complete control of Congress over inter-state commerce so far as navigation was concerned. The deeper significance of this interpretation of the commerce clause appeared only when railroads began to span the continent and the jurisdictional lines of States were crossed and re-crossed by an ever-increasing volume of trade. Twenty-five years had wrought a vast change in the position of the national judiciary in the American constitutional system. "It is now seen on every hand," wrote Attorney-General Wirt, urging the appointment of Chancellor Kent to a vacancy on the Supreme Court bench, "that the functions to be performed by the Supreme Court of the United States are among the most difficult and perilous which are to be performed under the Constitution. They demand the loftiest range of talents and learning and a soul of Roman purity and firmness. The questions which come before them frequently involve the fate of the Constitution, the happiness of the whole Nation, and even its peace as it concerns other nations." In the light of the decisions reviewed, the nationalizing tendency of the federal judiciary is unmistakable. But a constitutional reaction had set in; and even while John Marshall was setting forth the doctrine of national sovereignty in its most uncompromising form, John C. Calhoun in the quiet of his estate in South Carolina was elaborating a defense of state rights on premises which the great Chief Justice had combated for a quarter of a century. BIBLIOGRAPHICAL NOTE