Socialist Cities is a comparative treatment of grass-roots Socialist successes. It marks the first comprehensive look at the urban working-class base of the American Socialist movement in the early part of the century, and reveals the importance of municipal politics as an organizing strategy.

The author assesses the reactions of both workers and non-workers to the party, and provides a fresh perspective on the perennial question of why socialism 'failed' in America. He demonstrates that the subtle and ongoing dialogue between the party's own internal theoretical and tactical weaknesses and the broader class and structural obstacles against which it struggled, contributed to its failure.