Racism was becoming more and more practical. Edmund Morgan, on the basis of his careful study of slavery in Virginia, sees racism not as "natural" to black-white difference, but something coming out of class scorn, a realistic device for control.
"If freemen with disappointed hopes should make common cause with slaves of desesperate hopes, the results might be worse that anything Bacon had done. The answer to the problem, obvious if unespoken and only gradually recognized, was racism, to separate dangerous free white from dangerous black slaves by a screem of racial contempt."
A Peoples's History of the United States. Howard Zinn