The simple act of separating ourselves from others based on characteristics such as colour (or religion, or ethnicity, or sexual inclination) is inherently racist, sexist, religionist, etc.. "I choose to be with people like me, and people not like me should not seek to join our club." That's not a healthy way for humans to live on our crowded little planet.
MLK was quite right -- we must accept everyone who is not behaving very badly, though we do not need to make everyone our friend. But when you make your friends based -- not on their colour, their ethnicity, their sexuality, their gender, their religion -- on the content of their character alone, then you may be getting somewhere.