What are the motifs in The Power Broker: Robert Moses and the Fall of New York by Robert Caro?

A recurring idea is politics and power. Nothing can be accomplished within the Tammany Hall system unless it is done the Tammany way. Moses does not have any political affiliations per se. He does not come up through the Tammany system either. Early in his career he develops a plan for civil service reform that infringes on the power of the Tammany system and directly challenges that power.