To what extent was Progressivism an expression of America’s old utopian tendencies reacting to the challenges of the industrial age?
Progressivism was most definitely an expression of the utopian tendency in American attitudes. It was the response of people with such utopian ideas to the new challenges presented by the industrial age.
Since the US was first created, many Americans have felt that they could, with enough work, create a perfect society. If they fell short, they would at least be able to improve society in important ways and work toward perfection. During the industrial age, things seemed to be moving in the wrong direction. The country seemed to be getting taken over by rich industrialists on the one hand and poor immigrants on the other. At that point, people with utopian ideals started a movement to take power away from (as they saw it) the greedy rich while, at the same time, working to uplift the poor immigrants. These reformers hoped to create a utopia where all people shared the same communitarian and sober values that the reformers themselves held.
It is therefore accurate to say that the Progressive Era was an extensive reaction of utopians to the new problems of the industrial age.