What term best describes the u. s. government's policies towards businesses in the late 19th century?

During this period, the U.S. government took an aggressive stance against many business and industrial establishment who were using unfair practices to accumulate wealth and monopolize industries.  It went after several industrialists and passed several laws that prohibited unfair practices as well as business strategies that helped form monopolies.

answer; decipher the motives for why people behave the way they do;