Look, back in the day, it was easier to just call the offspring of any white-black union black, and enslave them. Profitable, too! There were daddies selling their own kids into slavery (and angry, jealous wives as well). The idea that a mixed-race person is “assigned” by the powers that be into the “lowest” racial stratum is called hypodescent; set up to keep the People In Power in power and with access to all the good stuff. I feel that that has been the entire point of racism/classism/sexism in the world, to keep the resources and privilege in as few hands as possible.
It’s not like American chattel slavery was that long ago in historical terms – only 140 years – so Americans are still shaking off this idea that people with any African descent are inferior to the descendants of Northwestern Europeans. It’s not that we’re inferior, it’s that certain Euros got their hands on the good stuff here and want to keep it. I don’t like the mindset and am working on my part to change it, but I understand it. Read How the Irish Became White or How the Jews Became White or how the Italians and other non-Anglo-Europeans became white in this country. Anything to keep African-Americans from being the equals of whites. Feh.
And bottom line, that’s the thing the US battles with regards to black people. If someone has attractive personality characteristics, white folks will say, “Oh, well, you’re not like those people”, or “You’re not really black.” I know, because I still hear these things in 2010. Yet, even with light skin and long, wavy hair, I’ve still been stopped by white cops and asked for ID for walking around in white neighborhoods. In America. These cops weren’t looking to ask me out, but assumed that I was casing their neighbourhoods. :P
My maternal grandmother (seriously, one drop) passed for some time until she met and married my not one-drop-of-anything-else-but-African grandfather. Good for Obama for making his one statement, but otherwise not addressing this stuff, and getting on with the business of governing.