THE Civil War began over a simple question: Did the Constitution of the United States recognize slavery — property in humans — in national law? Southern slaveholders, inspired by Senator John C. Calhoun of South Carolina, charged that it did and that the Constitution was proslavery; Northern Republicans, led by Abraham Lincoln, and joined by abolitionists including Frederick Douglass, resolutely denied it. After Lincoln’s election to the presidency, 11 Southern states seceded to protect what the South Carolina secessionists called their constitutional “right of property in slaves.” The war settled this central question on the side of Lincoln and Douglass.

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