Why are people so ignorant when it comes to race?

OMG! I just read the most ignorant, heartbreaking question ever. Thank god it was just deleted. Someone asked if we should bring lynching and slavery back. Then they went on to say horrific things about black people. My mouth was just lying on the floor, I couldn't believe that someone was out there talking about it's time to chain those up again. Thank God it was deleted. Topics like that are so touchy to the black race, to any race. Why are people so ignorant today when it comes to race? As far as I'm concern there is one race, the human race.