This is a partial transcript from On the Record with Greta Van Susteren, March 11, 2004 that has been edited for clarity.

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GRETA VAN SUSTEREN, HOST: More than 190 people are dead after terrorist bombs exploded in trains and stations along a commuter rail line in Madrid (search), Spain, on Thursday.

What's to stop a similar attack from happening here in the United States? Joining us from Washington is national security reporter Bill Gertz of The Washington Times.

All right, Bill, what's to prevent it from happening here in the United States? Our subways and trains are virtually unguarded.

BILL GERTZ, WASHINGTON TIMES: There is almost nothing preventing a major terrorist attack on a train, even here in the nation's capital. There is a long section of a train tunnel that passes right under the Capitol, which is highly vulnerable. I've talked to a number of security officials who are very concerned about it. The ultimate nightmare scenario there is that one of these freight trains carrying some kind of chemicals could be exploded underground and you'd have a huge disaster in the Capitol. The train system is very, vulnerable, not just in the major cities, where you have subways, as well, but also around the country, especially further out west.

VAN SUSTEREN: You know, Bill, sometimes viewers complain that we may be sending signals to terrorists by telling them the trains and subways are unguarded. But it certainly is no secret. You get on a train, and no one checks their package. I don't know if that may paralyze transportation if we did have some sort of security system. But this is no secret, is it?

GERTZ: No. And it's a totally different system than the airline system. You know, we've really tightened down security. You can't get near an airliner without going through several levels of security. That's not the case with trains. And of course, the more local you go, the easier it gets, of course, in a mass transit subway in major cities and then some of the national Amtrak lines, as well.

VAN SUSTEREN: Why isn't anyone doing anything, Bill? I mean, I assume the authorities have contemplated this. But why isn't something being done? Is there nothing to do?

GERTZ: Well, it's the job of the Department of Homeland Security. I think they're aware of it. They're trying to get attention focused on the problem. And frankly, it's been very difficult. I've talked to a number of rail security people who say that we just don't have enough people to protect these systems.

VAN SUSTEREN: All right. But you say not enough. Is anything at all being done?

GERTZ: Well, there's no question that they have sent out alerts and that the mass transit system has been a target of Al Qaeda. You know, Khalid Shaikh Mohammed disclosed to debriefers last year that there was a plan to firebomb the D.C. subway in a section between Capitol Hill and downtown D.C. Luckily, that plot was never carried out, but it's an indication that these are the kinds of things that Al Qaeda is thinking about, how to do underground rail terrorist bombings. I think when it all comes down, I think we're going to find out that this bombing in Madrid was probably Al Qaeda, although it's still too early to say.

VAN SUSTEREN: What are your intelligence sources saying? Are they worried that – as Mike Emanuel reported -- at least in one written communication, they say they're 90 percent ready to hit the United States again, but the U.S. has cautioned they have lied and exaggerated, sent false communications before. Nonetheless, that's not a nice note for us to be hearing about tonight.

GERTZ: Right. And I think what we'll be hearing in the next few day that they'll probably be not raising the alert level, but at least alerting security officials on mass transit and rail systems around the country that they're going to tighten up security.

VAN SUSTEREN: But tighten up what security? I mean, that's my whole point. If there is no security, you can't very well tighten it up.

GERTZ: Well, it is true. One official told me that anybody could walk up to a slow-moving freight train and plant some kind of device on it. It's a tough question. I think they could do it if they increase security patrols around key areas. But it's going to be very difficult to watch the entire rail system. No question about that.

VAN SUSTEREN: And of course, I find that astounding, with the number of rail systems, subways, if all of a sudden tonight, we got to try to do something, we simply don't have the manpower.

Let me turn quickly to this woman who was arrested in Maryland as a spy for Iraq against the United States, an American woman. Not exactly a spy, right?

GERTZ: Right. The FBI regards this suspect as what they call an agent of influence. Not a real espionage person, someone who is trying to get information or transfer information. Her job seemed to be to kind of carry water for the regime of Saddam Hussein, and I think that if it ever goes to trial, that's kind of what they're going to show. I talked to some intelligence officials who told me that they were able to detect this woman through her contacts in New York with Iraqi diplomats, and that they were able to confirm those contacts and her role with supporting Iraq through documents obtained from the Iraqi intelligence service in Iraq after the war.

VAN SUSTEREN: All right, Bill. Thank you.

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