How, we wonder today, could such otherwise enlightened and exemplary men as George Washington and Thomas Jefferson have owned slaves, a practice so contradictory to all they stood for?
There is no easy answer to such questions. But surely a part of the answer is that each of us is born into a world that we did not make, and it is only with the greatest effort, and often at very great cost, that we are ever able to change that world for the better. Moral sensibilities are not static; they develop and deepen over time, and general moral progress is very slow. Part of the study of history involves a training of the imagination, learning to see historical actors as speaking and acting in their own times rather than ours; and learning to see even our heroes as an all-too-human mixture of admirable and unadmirable qualities, people like us who may, like us, be constrained by circumstances beyond their control. . . .
The ambivalences regarding slavery built into the structure of the Constitution were almost certainly unavoidable in the short term, in order to achieve an effective political union of the nation. What we need to understand is how the original compromise no longer became acceptable to increasing numbers of Americans, especially in one part of the Union, and why slavery, a ubiquitous institution in human history, came to be seen not merely as an unfortunate evil but as a sinful impediment to human progress, a stain upon a whole nation. We live today on the other side of a great transformation in moral sensibility, a transformation that was taking place but was not yet completed in the very years the United States was being formed.
~ Wilfred M. McKay