By 1901 the reform upheaval was too strong to be contained within state boundaries. Moreover, certain problems with which only the federal government was apparently competent to deal cried out for solution. McKinley might have succeeded in ignoring the rising tide of public opinion had he served out his second term, but McKinley’s assassination in September 1901 brought to the presidency an entirely different kind of man—Theodore Roosevelt, at age 42 the youngest man yet to enter the White House. Roosevelt had broad democratic sympathies; moreover, thanks to his experience as police commissioner of New York City and governor of New York state, he was the first president to have an intimate knowledge of modern urban problems. Because Congress was securely controlled by a group of archconservative Republicans, the new president had to feel his way cautiously in legislative matters, but he emerged full-grown as a tribune of the people after his triumph in the presidential election of 1904. By 1906 he was the undisputed spokesman of national progressivism and by far its best publicity agent. (The White House was, he said, “a bully pulpit.”) Meanwhile, by his leadership of public opinion and by acting as a spur on Congress, he had revived the presidency and made it incomparably the most powerful force in national politics.

McKinley, William: assassination Leon Czolgosz assassinating U.S. Pres. William McKinley, 1901. Photos.com/Thinkstock

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In 1901, Americans were perhaps most alarmed about the spread of so-called trusts, or industrial combinations, which they thought were responsible for the steady price increases that had occurred each year since 1897. Ever alert to the winds of public opinion, Roosevelt responded by activating the Sherman Antitrust Act of 1890, which had lain dormant because of Cleveland’s and McKinley’s refusal to enforce it and also because of the Supreme Court’s ruling of 1895 that the measure did not apply to combinations in manufacturing. Beginning in 1902 with a suit to dissolve a northwestern railroad monopoly, Roosevelt moved next against the so-called Beef Trust, then against the oil, tobacco, and other monopolies. In every case the Supreme Court supported the administration, going so far in the oil and tobacco decisions of 1911 as to reverse its 1895 decision. In addition, in 1903 Roosevelt persuaded a reluctant Congress to establish a Bureau of Corporations with sweeping power to investigate business practices; the bureau’s thoroughgoing reports were of immense assistance in antitrust cases. While establishing the supremacy of the federal government in the industrial field, Roosevelt in 1902 also took action unprecedented in the history of the presidency by intervening on labour’s behalf to force the arbitration of a strike by the United Mine Workers of America against the Pennsylvania anthracite coal operators.

Roosevelt moved much more aggressively after his 1904 election. Public demand for effective national regulation of interstate railroad rates had been growing since the Supreme Court had emasculated the Interstate Commerce Commission’s (ICC) rate-making authority in the 1890s. Determined to bring the railroads—the country’s single greatest private economic interest—under effective national control, Roosevelt waged an unrelenting battle with Congress in 1905–06. The outcome—the Hepburn Act of 1906—was his own personal triumph; it greatly enlarged the ICC’s jurisdiction and forbade railroads to increase rates without its approval. By using the same tactics of aggressive leadership, Roosevelt in 1906 also obtained passage of a Meat Inspection Act and a Pure Food and Drug Act. Passage of the former was aided by the publication of Upton Sinclair’s famous novel, The Jungle (1906), which revealed in gory detail the unsanitary conditions of the Chicago stockyards and meat-packing plants.

Union Stock Yards: beef processing Beef processing as conducted at the Union Stock Yards, Chicago, c. 1900. Geo. R. Lawrence Co./Library of Congress, Washington, D.C. (LC-USZ62-52728-9)

Meanwhile, almost from his accession to the presidency, Roosevelt had been carrying on a crusade, often independent of Congress, to conserve the nation’s fast-dwindling natural resources and to make them available for exploitation under rigorous national supervision. He withdrew from the public domain some 148,000,000 acres of forest lands, 80,000,000 acres of mineral lands, and 1,500,000 acres of water-power sites. Moreover, adoption of the National Reclamation Act of 1902 made possible the beginning of an ambitious federal program of irrigation and hydroelectric development in the West.