The Age of Reform (1955) by Richard Hofstadter (http://en.wikipedia.org/wiki/Richard_Hofstadter) is a landmark in American political thought. It examines the passion for progress and reform that coloured the entire period from 1890 to 1940 – with startling and stimulating results. It searches out the moral and emotional motives of the reformers, the myths and dreams in which they believed, and the realities with which they had to compromise. A Pultzer Prize winner in 1955 and well worth reading half a century on.
For a summary of the contents refer to http://en.wikipedia.org/wiki/The_Age_of_Reform
352 pages in Random House, USA paperback edition
ISBN 978-0394700953
Richard Hofstadter