So...MLK didn't actually say what you think he said.
What he said was that the dream isn't about being colorblind, it's about finding equal value in all races.
But because you're lazy, you don't really give things much more thought than superficial face-value...a trait you share with Conservatism.
Here's a terrific piece, by a black writer (someone whose name you might recognize) that digs into the meaning of the speech and that line in particular:
REGGIE JACKSON: MLK’S “DREAM” WAS NOT ABOUT BEING COLORBLIND BUT SEEING THE SAME VALUE IN EVERY COLOR
http://www.milwaukeeindependent.com...nce from the,calling for a colorblind society.