I think it's a matter of interpretation

While I want to see an investigation into this, particularly with admissions by Bush officials that treatment of detainees met the definition of torture, preferably by a bipartisan panel, I don't think this exchange (From Larry King) is necessarily the smoking gun that Andrew Sullivan does:

KING: So there's nothing you've done in the area of treatment of prisoners that causes you any kind of pause?

G. BUSH: No. No. Everything we did was -- you know, it had legal -- legal opinions behind it. Look, you're sitting there, you've captured Khalid Sheikh Mohammed. He's the guy that ordered the September the 11th attacks. And we want to know what he knows in order to protect the United States of America. And I got legal opinions that said whatever we're going to do is legal. And my job is to protect you, Larry. And I've given it my all. I've given it my all.

I think there's a question of interpretation here. In my mind there are two ways to interpret what he's saying. One way is the way Andrew Sullivan does, that W. asked for justification to allow him to do what he wanted to do. The other way to look at it is that W. stated he asked if he COULD do what he wanted to do. I can't say without more context, particularly with tone or investigation, which position is more correct.