Why was the Progressive Era a turning point in U.S. history towards making the government more activist and accountable to the people?

The
Progressive era, which lasted from the 1890s to the 1920s, gained steam due to the financial
panic of the 1890s and ended at the close of World War I. During this time, the financial
collapse made people open to new ideas, with many believing that a system that seemed primarily
to benefit the so-called "robber baron" industrialists and corrupt politicians had to
change. Immigration had skyrocketed, and the country, though still largely rural, was growing
increasingly urban. The large pockets of people crowded into cities made government-level action
more imperative: people simply could not solve problems created by industrialism on their
own. 

Improvements in technology made it easier to take indoor photographs in
poor light. This made it possible for a journalist like Jacob Riis to document the terrible
living conditions of the poor in urban tenements, leading to an outcry, and the impetus for
government action. Upton Sinclair's  The...

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