Why give Murtha the time of day? The libs have popularized the idea that we’re losing this war with statements like those made by Murtha. Pretty soon, they’ll have the public believing that Petraeus is a political hack.
Why? Because Murtha is a member of a "Sacred Cow" organization-- a veteran, a mother or widow of a fallen soldier, a minority, etc. If they say something, the media believes they're beyond criticism (especially if it agrees with their agenda). Murtha and the media are playing on this "sacred cow" reputation just like they did with Cindy Sheehan and the "9/11 widows."
Note, however, that the "sacred cow" does not apply to members currently working for the establishment; in fact, it is the opposite. If they can pit one against the other, the media will jump all over the chance to do it.