Bunch of little things, mostly. But the racial example is a large part.
I grew up a white kid in strictly segregated small Texas town. No black friends, hell, hardly ever saw a black person, unless you looked across the tracks. I had no ill feelings against black people, because I had no feelings about black people. I mean, it was WHITE!
When I joined the Air Force, the world had just changed, and any display of racism could end your career. But there were not many black guys, so I still did not mingle much. After a few years in training and short assignments, I was placed on a B-52 crew where the pilot, the aircraft commander, was a very large black guy. Our crew was destined for combat in South East Asia, and I did not know what to expect. But it turned out that my boss had a good sense of humor, liked movies, music, good food, booze, shopping for cameras and hi-fi in the Japanese markets,... same as me, and we got along great! And I became color-blind, except for noticing a subtle difference.
Through out my life, I met many black guys, became friends with a few, but I always felt they had a strange attitude. A defensive, reservation against getting too close. Except for one--Charlie would just come to the cafeteria full of co-workers, and sit at a table full of white guys without that cautious, careful check to see who he was sitting by. He thought he was one of the guys. Turns out, that Charlie was born and raised in the Virgin Islands--he did not know he might not be one of the guys, because he had not been exposed to the every-day racism of American life as a child.
As I thought about it, I remembered the dismissal of every aspect of blackness from my early life, by my friends and relatives and parents. The blacks were made to feel second-class, by the whites, and by their families. Who knows how many times a bright, capable black kid, had been set down by his father (who had been horribly discriminated against) and told "You dont have a chance kid, no matter how much you try, you dont have a chance, whitey aint never going to give you a break." And I wondered how many black kids otherwise just like me, had turned to gangs, drugs, crime and violence, because my father and grandfather, would not have given his father and grandfather a chance. And I felt a little guilty.
So, I voted for Obama, largely, so that when some black kid's dad says "you dont have a chance", there will be Obama on TV, President of the United States, and that kid can think, "Maybe dad is wrong on this one." And I could think, by electing Obama, maybe I can help bring Americans together a little. And I will again.
And, what the hell, the unnecessary-wars+tax-cuts of George W, made me want to puke, and never vote for the GOP again.