Let me quite plain: the first thing I thought when I saw this is "What the h*** is he running for? Manchurian Candidate in Chief?" No, that's neither nice nor fair, so I offer the thought with caveats.
But in 2008, I'd rather not re-fight the Vietnam War by proxy. And I'd rather not fight our current war indefinitely. At the last thing we need is a scold in the White House.