This is a very interesting study of an all-too-neglected era in Mormon history. Reed Smoot was elected as a U.S. Senator in 1902, after he had already become a Mormon Apostle. Not satisfied that Mormons had really put polygamy behind them and disconcerted by reports of purportedly subversive temple oaths, the Senate conducted three years worth of hearings on the manner in an attempt to unseat the Mormon Elder.
Flake examines how the Smoot Hearings became a catalyst for change in the Mormon Church and in the United States, forcing the two to come to terms with each other. The Church, on the one hand, finally agreed to subordinate itself completely to American law. While the United States Government, on the other hand, finally agreed to cede Protestant hegemony to some extent and recognize the Mormons' right to exist.
Along the way, Flake details just how vitriolic and widespread anti-Mormon sentiment remained early in the last century and the difficulty facing Church leaders attempting to maintain a religious identity in the midst of coerced doctrinal upheaval. Ultimately it was Joseph F. Smith's (nephew of the founding Prophet) renewed emphasis on the Church's foundation of continuing revelation that successfully brought Mormons to terms with change and paved the way for the modern Mormon identity.
The Smoot Hearings were a pivotal moment in the history of the Mormon Church and the development of religious liberty in this country. My only issue with this work is that I tend to believe it overstates just how much polygamy contributed to Mormons' sense of identity.
For anyone interested in the subject, I also highly recommend the biography of Joseph F. Smith, by his son Joseph Fielding Smith. Joseph F. is by far the most interesting person in the whole ordeal, and the biography, though not scholarly, provides a great look at the man and prophet.