This is a partial transcript of "The Big Story With John Gibson," Nov. 18, 2004, that has been edited for clarity.

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JOHN GIBSON, HOST: Iran still says that its nuclear program is for energy only, but Colin Powell (search) says he believes Iran is working on missiles that could be fit with nuclear weapons. And an Iranian opposition group says Tehran is enriching uranium at a secret facility unknown to U.N. inspectors.

Joining me now from Washington, American Enterprise Institute (search) Resident Scholar Michael Ledeen (search). Michael, the big question: so should we be worried about Iran's nuclear ambitions?

MICHAEL LEDEEN, AMERICAN ENTERPRISE INSTITUTE, RESIDENT SCHOLAR: Of course. We are worried, we have been worried. Everybody's worried. The question's not should we worry, the question is what can be done?

GIBSON: Well, what can be done?

LEDEEN: Well, there are two things that can be done. One is to just address the nuclear problem in and of itself and try to find either some deal that they'll obey and stick to, which seems almost impossible. Or find a military way of taking it out as the Israelis did it in Iraq some years ago. Or, to go after the regime itself and to deal with the Middle East as a regional war, which is what it has been all along.

GIBSON: Michael, let's back up here. One of the reasons, one of the two reasons, we're talking about this today is that Colin Powell said almost offhandedly, as he's going out the door, "Oh, by the way, I have seen information that Iran is developing this missile that can carry a nuke and we ought to be worried about it. And so, there."

What did you make of Colin Powell's kind of strange statement?

LEDEEN: I was struck exactly the same way you were, which is — and I thought actually his statement was even stronger than what you described. I thought what he was saying was that we knew they had missiles and we knew they had a nuclear program. And what he said was they were studying ways to put the two together, so that they would have a nuclear-tipped missile that they could deliver.

Yes, why is he saying it now? Where has he been all along? If he's had this information, why hasn't he been more aggressive talking about Iran? And I think the answer is that the Europeans desperately do not want to deal with this problem. They want to hide from it. They have huge financial interests in Iran and they don't want to tackle Iran.

GIBSON: Well, the Secretary of State, Colin Powell's Undersecretary, John Bolton, has been screaming about this for months and months and months and the Europeans have said, "Let us handle it. We'll go talk to Tehran." What is the state of their talks? Abject failure at this point, or is there something encouraging?

LEDEEN: If the opposition group information is correct, then it is one more humiliation for the Europeans because time after time, they have announced that they had a deal with Iran and that Iran had agreed to suspend or stop or prevent uranium enrichment. And every time they've said that, then within weeks literally, we have found them cheating on that.

And, in essence, what the opposition group is saying is that the Iranians once again have pretended to suspend uranium enrichment, but they're secretly going ahead with it.

GIBSON: Yes, the opposition group — just so everybody's up to speed on this — has said two things in recent days. One is that Iran obtained a nuclear weapon design and enriched nuclear material from A.Q. Khan, the Pakistani who supplied the same stuff to Libya.

LEDEEN: Right.

GIBSON: So, "A": we should believe that, shouldn't we? A.Q. Khan was doing that and Iran is a logical customer.

LEDEEN: Well, my guess is that we know that because we've debriefed him extensively. I doubt that there's much that he did that we don't know about by now.

GIBSON: All right. The other thing that the opposition group said is it pointed at a specific secret facility where it says the Iranians are enriching uranium to make a bomb. Now, do we have the kind of specific information that the picture we're seeing now could actually be on the nose of a smart bomb as it descended toward a building?

LEDEEN: I don't know. I don't know the specifics. I don't have access to that kind of information.

However, the circumstantial evidence is that the Iranians have arrested a series of people involved in their nuclear program and are putting them on trial for espionage, for leaking secrets of the nuclear program to foreign governments.

Now, it stands to reason that if the Iranians weren't cheating on the deals and weren't involved in a military program, there would be no need for such trials.

GIBSON: And do you think the United States has the political will to run a raid like the Israelis did on Iraq and knock out their nuclear capability?

LEDEEN: I don't know. There's another question, which is: is a military solution to this problem possible, or is regime change the best way to go, as I've been arguing for many years.

You have in Iran, where the people hate the regime and want to bring it down. It would be a lot different to face an Iran that was Democratic and pro western with nuclear potential than this fanatical Islamist regime armed with nuclear weapons that they have promised as soon as they get them to use on Israel, right away.

GIBSON: Michael Ledeen of the American Enterprise Institute in Washington. Michael, as always, thank you very much. Appreciate you coming on.

LEDEEN: Thanks, John.

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