This letter of mine  appears in today’s edition of the Wall Street Journal:
Edwin Rockefeller accurately describes antitrust proceedings as “the debris of past political demagoguery” (Letters, July 10 ). Research shows that the 1890 Sherman Antitrust Act was not sparked by fears of high, monopoly prices: Real prices charged by the so-called trusts fell steadily during the decade leading up to the passage of that statute. Instead, that first national antitrust statute was the result of hostility to the low prices charged by the innovative entrepreneurs who pioneered the use of new technologies that, for the first time, enabled individual firms to serve a transcontinental market.
Populist hostility to the efficiency of firms such as Standard Oil filled congressional debate over the act. Congressman William Mason (R., Ill.), for example, thundered on June 20, 1890, that “Trusts have made products cheaper, have reduced prices; but if the price of oil, for instance, were reduced to one cent a barrel, it would not right the wrong done to the people of this country by the ‘trusts’ which have destroyed legitimate competition and driven honest men from legitimate business enterprises.”
Donald J. Boudreaux
The pioneering piece of research to consult here is Thomas J. DiLorenzo, “The Origins of Antitrust: An Interest-Group Perspective,” International Review of Law and Economics (June 1985).