First of all, I want to say that I think that the strength of the human race is in its diversity. We all know that if brothers and sisters have children they stand a higher chance of having congenital defects. To a lesser extent, the same could be said of intraracial unions. From that point of view, racists seem extremely misguided.
Most racists are against the acceptance of foreign people or cultures into their own. They shun diversity and feel that they are stronger by themselves. What I find fascinating is how people that call themselves open and welcoming treat racists the way racists treat foreigners. Basically, racists are pariahs and often can even be arrested for their ideas. If they aren't they become a non-functioning member of society. In that situation, some of them resort to violent or "sublime" acts in order to get themselves heard. Of course their targets will be the hard working members of cultural communities. In the end, society's knee-jerk reaction to people with different ideas ends up hurting those they are trying to protect.
Obviously, my conclusion is not that we should all be racists. It is that we should accept that others can think differently. It might even make us uncomfortable but we should be able to feel pride in knowing that we can listen to their viewpoints and form logical and civilized responses to them.