There are people reading my words right now who remember "whites only" signs. Imagine how shocked you would be to see one of those today. Yes, the change from that mentality was started with a social movement, but by no means did all of society agree by the time it was signed into law. Implementation was, in some places, painful. And certainly there is still plenty of hidden racism out there, discreetly tucked away, to be deployed only when someone can get away with it. But it's so much better than it was.
On a somewhat related note, please let's not glorify "the good old days" to such an extent that we pretend that only now at this point in history do people have to be made to value human life. People are people, and people have killed other people since the beginning of time. While I admire any effort to make us less wretched than we are at our worst (and I really do), the media has gotten so very immediate that our perception of reality is skewed (emotional appeals being more convincing than statistics). The good old days were really only good if you were male, wealthy, and white.