An influential Republican senator from 1881 until 1911, Nelson W. Aldrich (1841–1915) used his position on the Senate Finance Committee—which he chaired from 1899 to 1911—to maintain protection. Elected to the U.S. House of Representatives in 1878, Aldrich was selected in October 1881 to fill the Rhode Island seat vacated by the death of Senator Ambrose Burnside. As a member of the Finance Committee, Aldrich apprenticed under Justin Morrill of Vermont, who chaired the committee for twenty-two years, until 1898. An ardent defender of both the American System and Congress's authority over trade policy, Morrill opposed free trade, reciprocal trade agreements, and unconditional MFN treatment. When he assumed the chair of the Finance Committee, Aldrich remained steadfast to Morrill's views on trade.
Aldrich championed the position held by the Republican Party that economic nationalism promoted class harmony. By excluding competition from imports, so the argument went, a high tariff wall would promote the well-being not only of producers and workers but also of consumers. As Aldrich put it in the Congressional Record of 5 August 1909: "If we permit American industries to live by the imposition of protective duties, competition in this country will so affect prices that it will give the American consumer the best possible results." For Aldrich, the tariff was the price that overseas producers had to pay to enter the U.S. market. As such, protectionism placed the burden of generating revenue for the federal government on foreign producers and domestic consumers of imported "luxury" items.
Aldrich had a major hand in writing the McKinley (1890) and Dingley (1897) Acts, which allowed the executive branch to negotiate reciprocal trade treaties. However, he opposed the deals that administrations subsequently negotiated because they lacked equivalent exchanges of concessions. Wedded to the congressional committee system as the institutional basis for policy-making, Aldrich also fought the creation of a commission of experts to study the tariff "scientifically" and make policy recommendations. Committed to protecting the textile industries of his state, Aldrich obstructed the modest efforts of the Taft administration to reduce tariffs and sought to make what became the 1909 Payne-Aldrich Act as conservative a piece of trade legislation as possible.