The sad thing is that many people nod along to this sentiment, but in practice it seems to me that racism is alive and well in this country; it's just been driven underground. Certain words have been banned in polite company. Certain practices are illegal or no longer socially acceptable. But the irrational thinking and emotional responses are still there. (Case in point: the hysteria sparked by President Obama's "otherness." People who are uncomfortable with him can't flat-out say it's because he's a black man, so they cook up bizarre fantasies about him being a Kenyan Muslim socialist Manchurian Candidate, and then utterly refuse to accept any evidence to the contrary.)
The dream is still alive... but it hasn't been fully achieved yet. Someday I hope.