This was a joke, but really, racism is not insanity. I personally believe that racism is a natural condition, arising from protective xenophobia. In early days of humanity, "people not like us" were to be distrusted, at best, and killed at worst. The idea that all the various kinds of humanity just happily get along is, for me, quite unbelievable.
But as we learn more, we expand our definition of "who is like me". It is important in order to build a society that is greater than primitive tribalism. The world changes. We need to change with it.
But racism doesn't go away. It is deeply woven into our history and perhaps even into our genes. In order to overcome it and build a global community, we have to consciously, intelligently, make the effort to overcome our primitive, maybe instinctual distrust of "people not like us". And it is hard to do. I can't do it completely, even though I try. I admit, that in my heart, I am still afraid of "people not like me". Yes, I'm a racist. I admit it. I recognize it. I will do my very best to overcome my primitive feelings and be as unprejudiced as I possibly can be. But I will never succeed 100%. I will always be swayed, at least a little, by those distant callings. Damn it.