Towards the end of this morning's Senate Armed Services Committee hearing, Sen. Evan Bayh (D-IN) elicited the plainest assessment yet of the day from Gen. Petraeus.

Given the complexity of the situation in Iraq, Bayh wanted to know, "isn't it true that a fair amount of humility is in order in rendering judgments about the way forward in Iraq, that no one can speak with great confidence about what is likely to occur?"

Petraeus seemed to grow a bit irritated at the insinuation that he'd been painting an overly rosy picture. "It's why I've repeatedly noted that we haven't turned any corners, we haven't seen any lights at the end of the tunnel. The champagne bottle has been pushed to the back of the refrigerator. And the progress, while real, is fragile and is reversible," he replied.

Later, Petraeus again refused to venture any guess about when there might be further drawdowns of troops from Iraq after July.

A transcript of the exchange is below.

BAYH: Thank you, Mr. Chairman.

And thank you, gentlemen, for your patience and your testimony here today, and, most of all, for your service to our country.

We may have some differences of opinion about the way forward in Iraq, but none of us question your service to our country or the candor of your testimony today. So I'm grateful to you for that.

I have the privilege of serving on the Intelligence Committee as well as the Armed Service Committee. And I'm struck, in reading the most recent national intelligence estimate, which we can't discuss here in detail today, but both reading that and listening to your testimony here today and listening to some of the dialogue about how all of this is subject to differing interpretations.

And I would just ask you the question, isn't it true that a fair amount of humility is in order in rendering judgments about the way forward in Iraq, that no one can speak with great confidence about what is likely to occur? Is that a fair observation?

PETRAEUS: It is very fair, Senator, and it's why I repeatedly noted that we haven't turned any corners, we haven't seen any lights at the end of the tunnel. The champagne bottle has been pushed to the back of the refrigerator. And the progress, while real, is fragile and is reversible.

BAYH: In fact, reasonable people can differ about the most effective way forward. Is that not also a fair observation?

PETRAEUS: I don't know whether I would go that far, sir. Obviously I think that there is a way forward. I've made the recommendation on that. And so, I think, in that sense, that...

BAYH: General, you would not -- you would not mean to say that anyone who would have a different opinion is, by definition, an unreasonable person?

PETRAEUS: Senator, lots of things in life are arguable. And, certainly, there are lots of different opinions out there. But, again, if you -- I believe that the recommendations that I have made are correct...

BAYH: Here's the reason for my question, gentlemen. Just as I acknowledge your honor and patriotism, which I think is absolutely appropriate, I hope you would acknowledge the honor and patriotism of those who have -- look at this very complex set of facts and simply have a different point of view.

And, as you both are aware, some argue that to not embrace the assessment that you're giving us is, in fact, to embrace defeat or to embrace failure in Iraq. And I simply would disagree with those characterizations. And that was the reason for my question to you.

PETRAEUS: Senator, we fight for the right of people to have other opinions.

BAYH: As we should. And so I appreciate your candor with regard to that.