In Congressional debates in 1790 about the possible abolition of slavery, Georgia representative James Jackson attacked the abolitionist Quakers as...

James Jackson's words are not dissimilar to the popular Southern sentiment of the time: that slavery was a burden that the South had inherited from British colonial forebears; and that their only real choice was to maintain the system of bondage or free the slaves and be threatened with the possibility of being overtaken by its black population.

In states such as Virginia and South Carolina -- and later, Mississippi -- blacks outnumbered whites. There was palpable fear of black dominance. The reversals of all of the advances made during Reconstruction, including the elections of the first black Congressional representatives and senators, were a response to this fear of black power. 

Southern whites could not imagine a system in which blacks, whites, and however many Native Americans remained, simply co-existed. Moreover, to justify their refusal of co-existence, they deemed black people a separate species.

Nineteenth-century pseudosciences, such as phrenology, supposedly determined personality and intelligence by measuring skulls. Non-whites were somehow always deemed deficient in certain areas according to skull measurements. Phrenology was an outgrowth of craniometry -- interior skull-volume measurement. Craniometry was developed by the eighteenth-century Dutch scholar Pieter Camper. 

While on the one hand, we can forgive these early scientists and anthropologists for their errors due to the limitations of their respective times, they are guilty of pursuing a science of racial difference. These ideas were espoused by some American founding fathers, including Thomas Jefferson. In "Notes on Virginia," Jefferson famously wrote about his views on Native Americans and blacks. While he deemed the natives "savages," as did many of his contemporaries, he insisted that they could be civilized into gentlemen -- that is, assimilated into whiteness. Blacks, on the other hand, he deemed incorrigible and too low on the scale of humanity to be assimilated into white American society. 

Arguably, the cause for this view is purely economic. Native Americans, due to mortal illness and obstinacy, had not lasted as a steady slave supply. Poor whites had immigrated to work as indentured servants, working only in exchange for the promise of a parcel of land. After the Industrial Revolution, which had made cotton a necessity in the textile mills of Britain and New England, as well as the Louisiana Purchase in 1803 which provided the United States with prime cotton-growing territory (i.e., Alabama, Mississippi, Arkansas, and eastern Texas), there was no incentive to move away from slave-holding.

Whatever Jackson's personal moral discomfort may have been with slavery, if he possessed any at all, he probably thought it both politically and economically untenable for him and his Southern colleagues to support abolition.