Lincoln as Abolitionist (7)

However, by the 1820s, some Southern apologists for slavery began defending it as a positive good and an institution which deserved to be permanent. By the 1850s, that was the common defense of slavery in the Lower South. Indeed that was the principle written into the constitution of the Confederate States of America. In the Upper South states, like Virginia, the older justification was still heard even in the 1850s. (Robert E. Lee used it.)

And this was accompanied by pseudoscientific claims that the black race was inherently inferior to whites. Some of the more extreme defenders of slavery even claimed that the African race was an inferior species of being. Whites in the free states, where very few free blacks lived, shared a concept of whites as a superior race. But in the context of the 1850s, when when Lincoln said that whites would always have a "superior position" to blacks, it was a common assumption among virtually of his listeners that he was describing the relative position of whites and blacks in America in a matter-of-fact way.

This is to say that opposition to slavery and a belief in the equality of blacks and whites were not the same things. The former was far more common among the free states than the latter. Although again, it's important to remember that there were both free black and whites who did recognize an equality of rights among blacks and whites.

In fact, to a great extent, whites tended to equate the absence of slavery with the absence of black people. Historian William Freehling in The Road to Disunion (1990) decribes in some detail how slavery was weakened and eventually abolished peacefully in states like New York and Pennsylvania as the number of free whites came to greatly outnumber the black slaves.