It's a product of LBJ's "Great Society" program.
LBJ was a regular user of the N-word, and a dyed-in-the-wool democrat. He wanted blacks to become dependent on the government and vote democrat to ensure continued benefits. In fact, he said, "I'll have those <n-words> voting Democrat for the next 200 years."
It was that very moment the 'new' democrat party was born. The old slavery had to be denounced as evil so blacks would more readily don the chains of the new slavery.
Of course, it worked perfectly. And it was - and is - a national tragedy.