In her own words via Twitter: “I retweeted @JPBarlow using offensive language in a sarcastic tweet that was meant to slap back at racists after Obama's first election. Eh, not my best retweet, even if the intentions, both mine and Barlow's, were in the right place.”

Reading the RT itself, I think it’s clear she is AGAINST racism.

Wasn't that was a retweet (the good ole-fashioned retweet, starting with "RT")? It looks like it was a retweet from John Barlow, the founder of the EFF.

And it was definitely sarcastic, in nature. If you remove the loaded language, it's a bit easier to parse, I think: "If a black man was meant to talk to our schoolchildren, God would've made one President. Oh, wait, he did."

Ergo, a black man was, indeed, meant to talk to our schoolchildren.

That's exactly how I interpreted it as well. It is unwise to use slurs regardless of intent, because people are sensitive to them and rightly so. But her intent in using them was not to hurt or belittle.

You shouldn't remove it because it was a retweet, you should have removed it because it clearly meant the opposite of what you were implying it meant. Plenty often people get lampooned for statements that are later divorced from content but you are taking a single word and divorcing it from the content of the sentence it's in.