In tagging Rick Perry with the “painted-over rock” allegation without first learning the facts?

Yes, I think so.  It certainly is fine to point out that the name was offensive, but to suggest that Perry somehow was responsible was a bridge too far (transcript via MVOPOV):

WALLACE: I want to ask you, there is a troubling story on the front page of “The Washington Post” today about Rick Perry, governor of Texas, and it indicates that for years, his family had a hunting camp in west Texas and the name of it written on a stone was N-head. But, obviously, it wasn’t just N-head.

CAIN: Right.

WALLACE: And he was part of that camp even as governor.

Your reaction, sir?

CAIN: My reaction is, that’s just very insensitive. That is on a much — that is in a more vile negative word than the N-word and for him to leave it there as long as he did, before I hear that they finally painted it over is just plain insensitive to a lot of black people in this country.

I will chalk this up to Cain not being alert to the media’s (even Fox New’s) desire to create news on these shows.

Prof. Reynolds points out:

I think that Herman Cain hurts himself by joining in on these attacks.  His big appeal is that he’s not just another black race-card-playing politician.  Climbing on board with the Post’s hit piece suggests that actually, he is.  It reminds me of Tim Pawlenty’s weak and opportunistic reaction to the attacks on Sarah Palin.  I think that’s what killed his campaign.  If you side with the media establishment against other Republicans, you won’t help yourself in this election cycle.

What goes around comes around.  Defend one and defend all when the media plays the race card, the extremist card, or any of the other cards in their deck.

Update:  Cain clarifies: