After his election to the United States House of Representatives, McKinley quickly found himself faced with the necessity of taking a position on two issues that had emerged as important ones during the economic troubles of the middle 1870s: the silver and tariff questions. The first pitted the advocates of bimetallism against proponents of the gold standard. Although never a defender of unrestricted inflation, McKinley favored the remonetization of silver. Aware of silver sentiment among his constituents, he sought some means of securing bimetallism without inflation. He therefore rejected the advice of fellow Republicans and voted for the Bland-Allison Act of 1878, which authorized limited silver purchases and instructed the treasury secretary either to coin the silver or to issue silver certificates. Bimetallists hailed the act as only the first step toward remonetization of silver. Yet, with the return of prosperity and with limited silver purchases assured, agitation for soft money declined. When bimetallism again became the center of political controversy, McKinley was a candidate for the presidency of the United States.
While his vote for bimetallism was to cause him some embarrassment, McKinley concentrated his energies on the tariff, a matter he considered of far greater importance than silver. Upon entering Congress, he had wasted no time in making his position clear. He insisted that until the United States was able to meet foreign competition, high tariffs were necessary to the welfare of all classes. The tariff produced high wages, he asserted, and the laboring man had as great an interest in protection as did the manufacturer. McKinley's first action in the House was to submit a petition from workers who opposed tariff reductions, and in later years his name became synonymous with protection. An admirer of Henry Clay, he urged the extensive collaboration of all sections and classes in a harmonious new American system. The tariff was, in his view, a key measure for achieving national order and tranquillity.
McKinley helped write a protectionist plank for the Republican platform of 1888, and after Republican successes in the election that year, he presided over the House Ways and Means Committee. Because tariff duties were producing a treasury surplus and because disposing of the surplus invited corruption, reformers were demanding that rates be reduced. His mind again moving toward synthesis, McKinley saw the problem as one of reducing revenues without lowering the rates. He therefore proposed to resolve the issue not by accepting tariff reductions but by increasing duties on key items to the point where they became prohibitive.
Passed by Congress in 1890, the McKinley Tariff contained three innovative provisions. To prevent the importation of wheat and other foodstuffs from Canada and Europe, it established a schedule of duties on agricultural products. To satisfy consumer demand for lower sugar prices and to reduce the treasury surplus, it placed raw sugar on the free list while compensating domestic growers with a bounty of 2 cents a pound. Finally, at the insistence of Secretary of State James G. Blaine, it included a reciprocity section permitting the imposition of duties on products from Latin American countries that refused free entry to American products. Although the new tariff met criticism from reformers, who saw it as a measure to favor special interests, it at least helped to reduce the surplus while continuing protection. More important, McKinley became a convert to the idea of reciprocity, and to the end of his life, he urged such commercial agreements with other nations.