It's a lot like religion, I suppose. If you don't teach it to them when they're little, they'll never believe you when they're older.
That's why we tell cutesy bible stories, illustrated in cartoon fashion, and leave out the cruel, bloody bits.
Once upon a time, I saw a Phil Donahue episode. I think I was about 10 years old. Phil had a group of white supremacists on - a family in fact. There was a little boy on the show who seemed to be about my age. Seated in the front row were some truly astonished dark-skinned people.
I remember the boy's mother saying that, yes, they were teaching their son about the difference between the races. The quote is burned in my mind: "He knows that there are three kinds of people. There are men, there are women and there are n-----rs." They didn't bleep it out back then. With well-dressed, articulate black people staring her in the face, she enunciated her world view very clearly.
Then they asked the young boy if he knew what a "n----r" was. He didn't want to answer. His mother excused his shyness and told him to point one out as he definitely knew what one was. When the camera zoomed in on his face though, you could tell he wasn't shy. You could tell that he knew something was wrong. He knew that his parents had taught him something wrong.
Would that every child could be smart and skeptical enough to do the same. Sadly, that's not the case. If you really want to understand all of those "Strong GOP" states on the electoral map, all you have to do is understand the generation to generation passing on of racism.
Watch the first 20 seconds of this video. It's more disturbing, at least to me, as a parent, than all of the catcalls of "socialism", "communism", "muslim" and everything else.
(h/t: jhuth on Democratic Underground)