On March 6, 1857, Chief Justice Roger Brooke Taney of the Supreme Court delivered an opinion that, in the view of many, would decide the survival or the destruction of the United States. The bitter controversy over slavery that was dividing free states from slave states, North from South, was troubling the chief justice, a slave owner himself and a Democrat from the "border state" of Maryland. Although the verdict would settle one dispute between a slave and his master, Taney and the eight other members of the Supreme Court knew that it would do little to calm the controversy raging in the rest of the country. Not even the inaugural speech of the new Democratic president, James Buchanan, who had just appealed to "all good citizens" to accept the verdict no matter what it might be, would sway the opposite sides to...