How did Tarbell see Rockefeller role in developing the standard oil company?

Ida Tarbell viewed John D. Rockefeller as a shrewd and ruthless businessman who played a pivotal role in the rise of the Standard Oil Company. She criticized his monopolistic practices, highlighting how he used aggressive tactics to eliminate competition and secure a dominant position in the oil industry. Through her investigative journalism, Tarbell aimed to expose the unethical methods employed by Rockefeller, portraying him as a symbol of corporate greed and exploitation. Her work significantly contributed to public awareness and skepticism regarding monopolies in America.