I don't think he doesn't care what the opposition says. He thinks that most of the public doesn't care what the opposition says, and I'm afraid he's right. Media coverage (not counting blog coverage here folks) of Sheehan has been scarce thus far. I hope I'm wrong, and that Sheehan does become "a more powerful figure than [Bush] could ever imagine", but I'm doubtful.
Public relations-wise, this is an easy one, isn't it? If you're the President, you meet with Sheehan. You invite her in. You give her some lemonade. You listen. You say you're sorry. And then you let her go back out. PR problem over, no? Fuck, while she's talkin', you can have monkeys dancin' in your head. But doesn't this seem like a no-brainer?
Unless, of course, you don't give a shit. Unless, of course, you think of yourself as unquestionably right and, frankly, you couldn't give a happy monkey fuck what the opposition says. And, of course, Bush doesn't.
I almost completely agree with The Rude Pundit in this rant about the Bush/Cindy Sheehan standoff, although it's unfortunate he has to drag out the "liken my cause to Rosa Parks" meme.