In the troubled years leading up to the Civil War, newspapers in the North and South presented the arguments for and against slavery, debated the right to secede, and in general denounced opposing viewpoints with imagination and vigor. At the same time, new technologies like railroads and the telegraph lent the debates an immediacy that both enflamed emotions and brought the slavery issue into every home. Lorman A. Ratner and Dwight L. Teeter...