Maybe she was just diplomatically trying to avoid mentioning Iran.
That is a VERY sensitive issue right now, as was clear as the rest of that interview and the following Netanyahu interview unfolded . I have a feeling Iran will be in the news soon enough as it is. I got the feeling she didn't really want to talk about it. Incidentally, of course she's Obama's mouthpiece. That's her job. She's saying exactly what he wants the world to hear.
Besides, isn't David Gregory one of those Liberal Media Journalists that is always trying to give Democrats an easy interview? (See TB's post on Romney, below).