The Army of the Potomac was a hotbed of political activity during the Civil War. As a source of dissent widely understood as a frustration for Abraham Lincoln, its onetime commander, George B. McClellan, even secured the Democratic nomination for president in 1864. But in this comprehensive reassessment of the army's politics, Zachery A. Fry argues that the war was an intense political education for its common soldiers. Fry examines several key crisis...