I believe racism is acceptable under certain circumstances
Could you explain a circumstance that would justify racism?
I don't want to give a specific circumstance, but I do believe that racism may be justified under some circumstances.
It can be natural, and unavoidable, to make snap judgments about people based on their appearance.  However it behooves us to look beyond our initial impressions of people. When we are racist, we close ourselves off to the potential that each individual has, instead choosing to paint them with our own preconceived notions. When you're interacting with people of a different race, you should periodically check yourself to make sure that you aren't putting any unfair judgments on them.
I'm ok with racism. People already have been judging each other based on their skin tone.
Yes, it's true that this has been going on for most of human history, but that doesn't mean that it should continue.  Murder, rape, and robbery have also occurred throughout history, but those aren't acceptable today.  Together, we need to move beyond racism, and accept people for who they are.