I was pointing out that this difference of speaking style is not known to people here, unless they visit the US and hear it themselves.
That's why I wanted posters here to explain why it is that way (thanks, Xahar for the link) and why it's still that way after 400 years of Black settlement in the US.
My rudimentary understanding of it is this: the vast majority of African Americans draw their lineage back to the south as a result of slavery, and as such their predecessors spoke with a chiefly southern dialect. A large chunk of this population packed up and moved north and west in what were called the
great migrations, only to be indirectly segregated once again by class. The insulation of the ghetto allowed the southern accent they spoke to thrive far outside its original borders, and with conditions scarcely improving for them as time went on, their descendents retained many characteristics of the original accent.
This isn't a racist thing to recognize or ask, so I'm not sure what the objection is about.
