What is the author's style in A Bright Shining Lie: John Paul Vann and America in Vietnam by Neil Sheehan?

The language of this biography was well educated with undertones of anger. At times, the reader felt as though he or she were listening to a lecture on the history of the American Army and the political climate of the 1960s. The book contained a lot of information about the Army and the history that led to the war in Vietnam.