Interesting 1998 interview with John McCain conducted by Jason Vest for Mother Jones (ellipsis in original):
You not only have had combat experience in Vietnam, but you were also a prisoner of war. When you look at terrorism right now, with people like Osama bin Laden, do you have any reservations about watching strikes like that?
You could say, Look, is this guy, Laden, really the bad guy that’s depicted? Most of us have never heard of him before. And where there is a parallel with Vietnam is: What’s plan B? What do we do next? We sent our troops into Vietnam to protect the bases. Lyndon Johnson said, Only to protect the bases. Next thing you know…. Well, we’ve declared to the terrorists that we’re going to strike them wherever they live. That’s fine. But what’s next? That’s where there might be some comparison.
Not that many people were ahead of the curve on al-Qaeda in the 1990s, and we see here that John McCain was no exception. 9/11 made a lot of people think, though, that we should get more serious about fighting al-Qaeda. It made McCain think that we should invade Iraq.