If World War I was the most decisive event of the 20th century for Europe, its impact on the US was considerably less, but Schaffer shows that the war both presaged and contributed to the rise of federal power in the 1930s. Though exploring some subjects only superficially in his account, derived largely from secondary sources, and devoting a third of his text to the experiences of soldiers in the trenches, Schaffer still offers an illuminating overview of the impact of WW I on the US.