Yeah, the comparison was "deep-ended," but the false equivalence was so, from the get-go.
How about Deady to some notorious Nazi sympathizer who otherwise was a stellar character--- France, Italy, and Germany had many such.
It's not like slavery was some deep secret--- as some claim the Holocaust was (and since been absolutely refuted). Slavery went on for centuries before Deady, the Civil War (partly) was fought over it. And Oregon, being the last place in the US to have had an active KKK group, wasn't exactly a leader in opposition to it, even long after the fact.
Anyhow, I'm willing to bow to the concerns of kids of color who strongly have objected to it. It's not like this is a local issue, really. I wonder how many oppose this and also feel the Washington Redskins need to change their name? 
There's a saying in Portuguese: "Hot pepper on someone else's rump doesn't burn you."