Everyone knows by now that Sarah Palin doing that Katie Couric interview was a big mistake for Palin. But what they don't know, Palin writes in her new book, is that she only ever agreed to do it out of the kindness of her heart. In the spirit of sisterhood. Palin looked at Katie Couric, struggling in her new job at CBS, looking uncomfortable in her new power suit, trying so hard to prove you could be pretty and smart at the same time but not really having the gravitas to pull it off, and, well, she really pitied her. Why not throw the woman a bone? Palin reasoned. Show her how it's done:

She writes that she sat down with Katie Couric in part because she felt sorry for her, after Nicolle Wallace, a McCain aide, said Ms. Couric suffered from low self-esteem.

Well, this throws new light on Palin's upcoming interview with Oprah. We assumed she was doing it to promote the book, but now it seems clear she's just giving the host a chance because she's a minority with a weight problem.

Rolling Out Sarah Pailin's Side of the Story [Caucus/NYT]