I think Kevin Drum's focus on foreign policy "instincts" in raising a question like "Iraq aside, do you think Gore has fundamentally changed his worldview since the 90s in ways that Hillary hasn't?" is a mistake. It's worth considering principles. Iraq was premised on two big ideas. One was that unilateral preventive military force is a good way to handle non-proliferation policy. The second was that unilateral preventive military force was a good way to advance democracy. People who opposed the war, like Gore, believed that neither of those things were true. People who supported the war believed that one or both of those things was true.
I, for example, never really thought that invading random medium-sized dictatorships to try to turn them into democracies made sense. I did, however, believe that the use of unilateral military force as a tool of non-proliferation policy was a good idea. In retrospect, I, like John Edwards, no longer believe that. Does Hillary Clinton still believe it?
But to look at it from the "instincts" point of view, I'm not sure how much we can really conclude from looking at the Clinton years. I think the policies Bill Clinton enacted while in office were pretty good. At the same time, it's clear that the Clinton administration perceived itself, rightly or wrongly, to be making foreign policy under circumstances of tight political constraints. And, in particular, they believed that the tight political constraints made it unwise or impossible to pursue really big policy initiatives. That makes it hard to say exactly where anyone's instincts lay. It's clear that some members of Bill Clinton's administration left office feeling it was too bad that the political circumstances didn't exist that would make it possible to launch a preventive war in Iraq (Kenneth Pollack says as much in The Threatening Storm). It's also clear that some members left office feeling it was too bad that the political circumstances didn't exist that would make it possible to ratify the Kyoto Protocols (Al Gore, obviously). And some people probably thought both of those things.
And so on and so forth down the line. I don't find anything in the Clinton administration record terribly frightening. But it wasn't perfect either. There's raw material in there for a great foreign policy and also material in there for a terrible one. To me, the most troubling thing about Hillary Clinton is that her read of the politics is to always err on the side of hawkishness. And of course if she (a) votes for Iraq, (b) watches Iraq turn into an unpopular disaster, (c) declines to apologize for her actions, (d) wins the Democratic nomination, and (e) wins the presidency then that's only going to re-enforce that interpretation of politics. After all, if unapologetic support for a hugely unpopular foreign policy disaster doesn't even doom you in a Democratic Party primary, then why shouldn't you always err on the side of hawkishness?