By the early decades of the nineteenth century, Americans wondered, if slavery had become a necessary evil - economically essential but morally reprehensible.

A Necessary Evil? is divided into seven chapters: the first establishes the background for slavery in the new nation and sets the stage for the debate while the second chapter records the arguments over slavery from the Constitutional Convention. Chapters three, four, and five turn to the New England, Middle, and Southern states respectively and present the complete record of slavery and the ratification debate in these regions.

The next chapter demonstrates the peculiar institution's newly sanctioned role in the young republic and how abolitionists sought to reverse this growing consensus. Finally, the last chapter looks at slavery from the perspective of three of the most influential Americans, Washington, Jefferson, and Madison, to show the complexity and inner turmoil that surrounded slavery.