Gabriel Kolko's thesis, that the period from 1900 to 1916 was marked by the triumph of conservatism rather than reform, challenges traditional historical understanding of Progressivism. According to Kolko, business control over politics rather than attempts to democratize the economy via political means was the significant phenomenon of the Progressive Era. Federal intervention in the economy was undertaken frequently in response to the needs and demands of the industries to be regulated. Because they too were conservative, political leaders cooperated with representatives of business and finance in order to guarantee the preservation of existing social and economic relationships essential to a capitalistic society. "Liberals" were blinded to the truth of the political domination of big business by a "fetish" about the desirability of governmental regulation. The result of this alliance between government and business was the creation of a form of "political capitalism" by means of which economic interests obtained conditions of stability, predictability, and security through the utilization of political outlets. This essay is a case study of Kolko's thesis, concentrating on the establishment of the Bureau of Corporations, the only administrative antitrust measure of any consequence during Theodore Roosevelt's first term in office. In the case of the Bureau, direct business influence was negligible. President Roosevelt chose to support the Nelson amendment, which created the Bureau, instead of a more radical measure primarily for political reasons. He used public opinion to force a reluctant Congress to take action. Liberals who favored a much stronger bill were forced to acquiesce in the passage of the Nelson amendment not because they harbored a fetish about federal regulation of business, but because they feared the public would not understand a note against it. This study reveals that, in the case of the establishment of the Bureau of Corporations, Kolko overestimated the influence of key businessmen and the consensus of values between them and political leaders. He ignored the importance of ideological conflict in the debate over the Bureau and paid too little attention to the role of public opinion and strictly political considerations. Kolko's thesis offers little of value to an understanding of this episode in Progressivism.