[Paula Zahn, Cnn Anchor:] Our next guest knows all too well about biological warfare and those who wage it. Richard Butler is the former chief weapons inspector for the United Nations. He oversaw the efforts to dismantle Iraq's weapons of mass destruction, including its chemical stockpile. Good to see you again. Welcome.
[Richard Butler, Fmr. U.n. Chief Weapons Inspector:] Good to see you, Paula.
[Zahn:] I know it would be irresponsible for us to try to hype this anthrax story, but there are so many questions that we need to address. OK, government officials have basically told us that this particular strain potentially came from a lab in Iowa.
[Butler:] Right.
[Zahn:] We also know it was a strain that researchers all over the world had access to.
[Butler:] Right.
[Zahn:] How do you travel with this stuff.
[Butler:] Well, anthrax comes in the first instance as dried spores. Scientists then work on it and use it for research purposes, or to make chemical weapons. That bit gets harder. The particle size becomes very important, if it's to be a useful I said chemical, I meant biological, to be a useful biological weapon, particle size is quite important.
[Zahn:] Can you explain to us the the smaller...
[Butler:] Well, if it's too small, it won't do the job of getting into the lungs and killing a person. If it's too large, it will fall to the ground and won't be dispersed in the air in the way that a person wanting to deliver a biological weapon would want it to. Particle size is critical to the effectiveness of this stuff as an awful weapon. I hope that puts it the simplest.
[Zahn:] Yes, OK, so we know that three people got sick from this anthrax, the spores. it will fall to the ground and won't be disbursed in the air the way a person delivering a biological weapon would want it to. Particle size is critical to the effectiveness of this stuff as an awful weapon. I hope that puts it the simplest. Paula: so we know three people got sick from this anthrax the spores.
[Butler:] Right.
[Zahn:] What does it suggest to you, that they were these larger particles then? I know there was a lot of speculation.
[Butler:] That they were the right size, that they were the right size to do that job. What I understand, Paula, is that what has been detected in Florida was synthesized. In other words, it didn't occur in nature, so a person did this.
[Zahn:] Now the attorney general wouldn't go that far this morning, but a lot of other people are saying exactly what you're saying this morning. I asked him the question whether it was organically grown or whether it was manmade, and he said it is simply too early to tell, but his suspicions are the latter.
[Butler:] Right, well, I will defer to him. The advice he is getting, obviously, is telling him to be cautious. But my belief is that this didn't occur in nature, OK, that someone synthesized and made this, a person did it. Then the question becomes, who is that person? Was it a terrorist, or just some loony out there, thinking because of the tragedy I shouldn't call it a tragedy, because it's more than that the outrage of one month ago today that this provides an interesting background to scare people. And so, I mean, there are people who would do that. We don't know. And I think it's critical for us to be very careful about finding out exactly who did this.
[Zahn:] How do you get this stuff? We know there are a bunch of scientists that left the Soviet program when the Soviet Union dissolved. We had a guest the other day that said 7,000 of them are working for a lot of different foreign countries on biological weapons.
[Butler:] But there are two different questions, two different parts to the good questions you just asked, how do you get the stuff? There is the stuff itself, and there is the know-how to make it, to make it into a weapon. That's where the scientists come in. And there are a lot of them around, including some disaffected and unhappy people from the former Soviet Union. That is true. The material itself, the raw material, is actually distressingly easy to obtain. When you obtain it, it is in an inert and undangerous form. It then has to be transformed into a weapon or for some other scientific purpose. So there is the material and the know-how. The material is easy to get.
[Zahn:] All right, so explain to us the know-how that would have been required to get these spores inside the AMI building. Are they microscopic? Do you see them inside the letter?
[Butler:] It seems it may have come in a powder form. That's the residue that was apparently on the computer keyboard of poor Mr. Stevens who died. There was a letter apparently that came to the mail room with a powder in it. It could be done that way, or it could be dispersed through the atmosphere, for example, through the air system of the building. You need the material. That's easy to obtain. It is much harder to then make it into a weapon, and that's where you need scientific know-how. And then finally...
[Zahn:] You are telling me whoever did this knew a fair amount about how to turn inert anthrax into a biological weapon.
[Butler:] Then they have to deliver it. The FBI is looking into it. They obviously need to know exactly what kind of transformation of the material took place, what kind of anthrax this was, then they need the delivery route, and hopefully that would tie back to persons who did this.
[Zahn:] And as I understand, that's pretty pro forma, because they have this particular strain typed. It is a matter of matching it up with different labs around the country who have access to it? Is it as simple as that, or is it more complicated?
[Butler:] It should be relatively straightforward, and the sample laboratory from which scientists obtain the basic raw material is quite a public one, and it should have records of which persons, which scientists sent for the basic raw material. This should be a trial there that would be able to be followed and lead hopefully to the culprit.
[Zahn:] Are you confident the culprit would be found?
[Butler:] Reasonably. Reasonably. Unless, now it gets darker, unless it was terrorism, unless it did have something to do with the people that turned the aircraft into missiles a month ago today, and that they obtained chemical weapons from another source, such as Iraq. Then I think it would be much harder. It would be more complicated, a darker scenario, and much harder to get to the bottom of.
[Zahn:] Attorney General Ashcroft also in my conversation with him would not confirm in a "Miami Herald" report, which is saying that Mohamad Atta, one of the suspected hijackers, actually had a subscription to one of the publications, one of the tabloids that AMI published.
[Butler:] So, that connects him to
[Ami. Zahn:] Right.
[Butler:] Whenever you are looking at the criminal activity, you need motive, means and opportunity. Maybe that subscription suggest a motive on his part, that he had some weird interest in AMI and its publications, or hatred for them or whatever, but it would appear to be a link, yes.
[Zahn:] And Mr. Ashcroft acknowledged that this morning, and I guess the FBI will continue to look into it. Right. Mr. Butler, as always, good to see you. Thank you for your insights.
[Butler:] Nice to see you. TO ORDER A VIDEO OF THIS TRANSCRIPT, PLEASE CALL 800-CNN-NEWS OR USE OUR SECURE ONLINE ORDER FORM LOCATED AT www.fdch.com