This research examines the U.S. economy in the early twentieth century in an attempt to reconcile the contradictory coincidence of regulated industrial and labor conditions with the systematic destruction of organized labor in the iron and steel industry. A modified version of social structure of accumulation (SSA) analysis is employed to demonstrate how different periods in American history may be construed as being governed predominantly by free market or regulatory mechanisms. This framework draws heavily upon the recent attempts of radical political economists to generalize SSA theory using the notion of an institutional structure. The modified SSA framework is then used to explore the specific institutional structure of the progressive era in American history to reveal its regulated character and provide the historical background for the more detailed case study of the iron and steel industry. The industrial case study provides support for the hypothesis that regulated periods tend to increase the rates of profit, output growth, and capital accumulation relative to free market periods. The enhanced performance of the steel companies was achieved as a result of a price and wage stabilization program initiated by the United States Steel Corporation. The case study also shows how this part of the Steel Corporation's regulatory program led to increased fluctuations in employment and longer working hours for the steelworkers. In an effort to combat potential threats from the federal government, the American public, and organized labor to the market stabilization program and mechanization drive, the steel companies introduced a paternalistic welfare program, company unions, and limited hours reform. The ultimate goal of the steel companies in maintaining the progressive era regulatory environment in the iron and steel industry was the indefinite continuation of the period's enhanced profitability. The study thus provides a solution to the contradictory nature of the industry during the progressive era and offers a general model for radical political economists who seek to use SSA analysis to investigate microeconomic questions in addition to the macroeconomic questions for which the framework was originally devised.