The history of Oregon shows a nasty history of racism.  Wasn't the cross on Skinner's Butte originally intended as a KKK warning to blacks on the RR to keep on going through the state?  It  is a tough call,  free speech is a right.  But also is the right to associate or not with anyone on the bases of what they say or do.  Would I want to be in a class and listen and find credible a teacher who made such an error in judgement?  Hard to say.  I think that forgive and forget is great, but remembering prior behavior, what a person or animal does and is capable of doing can help from getting hurt in the future.  And in the light of all the militant racists, white supremacists, neo-nazis, neo-patriot bigots etc who do exist in this country in pretty massive numbers and who do express dangerous statements and behavior, this professor's behavior pales in comparison.  Yet OTOH, because of the existence extremist racism, someone with her training should have known better.