Ideas that now seem like crackpot notions of race were, not long ago, regarded as common sense, and found themselves codified in law. The "one-drop rule" asserted that a single drop of black blood in an otherwise white citizen rendered that person black. Blackness was widely viewed as a contaminant that sullied white purity. (In antebellum America, white slave owners got around this problem by either denying the ordinary practice of raping and impregnating black women, or by justifying this predation as a racial improvement of the population of black slaves.) The rule was adopted by numerous state legislators in the first third of the 20th century, and used as the basis for Jim Crow laws.
In 1924 Dr. Walter Plecker, a public health advocate who worked for Virginia's Vital Statistics Department, said, "Two races as materially divergent as the White and Negro, in morals, mental powers, and cultural fitness, cannot live in close contact without injury to the higher." It wasn't until 1967 that the U.S. Supreme Court proclaimed Plecker's Virginia Racial Integrity Act and the one-drop rule unconstitutional. This decision, which eliminated the ban on interracial marriage, bore the wonderfully apt title of Loving v. Virginia.
Sadly but not surprisingly, such legal victories have not kept Plecker's sentiments from being embraced by contemporary guardians of racial boundaries. And, Barack Obama, the child of a black African father and a white American mother, is for these folks the very embodiment of what must not be brought together.
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