I think he's realized that he's in this way over is head and it's starting to take a toll.
OTOH, given his obvious diminished mental capacity, he may have simply forgotten to eat any food for the past couple of weeks.
"..Congressman John Murtha continues to make a fool of himself by suggesting we can effectively fight the terrorist insurgency in Iraq by "redeploying" our troops to a military base in Japan. Here's what he told Tim Russert yesterday in the course of arguing that we don't need a presence in Iraq to conduct the sort of quick-strike missions like the one that killed Abu Musab al-Zarqawi:.."
Quite a few people noticed the Meet the Press performance. I hope he loses his seat.