Preventing the Unthinkable

Focusing on the worst-case terrorism scenarios might not produce the best defense.

In early January, the chairman and ranking member of the Senate Homeland Security and Governmental Affairs Committee sent letters to 15 agencies requesting detailed information about their roles and readiness for thwarting or responding to a terrorist attack involving a nuclear or radiological weapon. The information is part of a broad inquiry by the committee into the nation's readiness to cope with these types of catastrophic strikes.

The committee wants to know the names, positions and authority of individuals responsible for responding to an attack. It also wants a detailed inventory of equipment and assets available for an emergency and a timeline for deploying them, as well as the names and positions of individuals most knowledgeable about those assets. Additionally, agencies are to specify their operational plans and training for a nuclear or radiological attack and provide the names of people with direct responsibility.

"We need to know where the federal government is in preventing the unthinkable from happening and preparing to deal with the consequences of a nuclear attack," says Chairman Sen. Joe Lieberman, I-Conn. "DHS Secretary [Michael] Chertoff has said that what keeps him awake at night is the prospect of a terrorist attack using weapons of mass destruction."

After the botched federal response to Hurricane Katrina two and a half years ago, Congress understandably wants to know how well prepared federal agencies are for something potentially much worse than a natural disaster. And they want the names of those responsible beforehand. Anxiety over a potential nuclear attack has been rising ever since the Sept. 11 terrorist attacks six and a half years ago. Plenty of experts have written books or

testified about the potential fallout, both literal and figurative, from a nuclear attack. Lawmakers and others routinely describe a terrorist hit involving radiological material-something far less damaging or difficult to achieve than a nuclear attack-as a matter of when, not if. Sting operations conducted by the Government Accountability Office, among others, have compounded such fears. In 2006, GAO investigators successfully carried weapons-grade uranium across the border from Canada in three out of four attempts.

In 2007, investigators set up a bogus company and acquired a radioactive materials license from the Nuclear Regulatory Commission, which they altered to obtain unrestricted equipment containing sealed radioactive materials from U.S. suppliers. They then found suppliers willing to provide enough material to build a dirty bomb.

Unquestionably, GAO investigators illustrated serious weaknesses in America's defense against nuclear and radiological terrorism (NRC immediately suspended its licensing program to address shortcomings before resuming; border security improvements are ongoing). But what's missing from discussions of vulnerabilities, says physicist Michael Levi, is a realistic understanding of what is involved in carrying out a nuclear terrorist attack. "Because it hasn't happened, it's easy to get carried away with our imaginations," says Levi, a fellow at the Council on Foreign Relations and author of On Nuclear Terrorism (Harvard University Press, 2007). "It's very easy to dream up fantastic schemes and worst-case scenarios and to take those to their policy conclusions."

He cites GAO's border security sting as an example of how nuclear terrorism is too often examined out of context. The sting responded to a genuine concern that terrorist groups would be more likely to try to move nuclear material across a remote stretch of the border, where security is much more difficult, than through ports of entry. "So someone [from GAO] drove up to the United States on the Canadian side of the border in an SUV, got out with a small gym bag holding four small canisters of weapons-grade uranium . . . carried it across the border about 10 meters, handed it to an accomplice and the accomplice moved on. Three out of four times, they succeeded," Levi says. "The immediate reaction when you look at something like that is to say there's a one-in-four chance of stopping a nuclear terrorist attack-this is absolutely unacceptable."

But the one-in-four odds also are inaccurate, he says, and distort our understanding of the vulnerability and its potential solutions. "First, remember this is only one part of a terrorist plot. A group has to go through a lot of things. A group has to acquire nuclear materials; it has to build a weapon or activate a weapon; then it has to move it around; and then it has to detonate it." With every step, the odds of success diminish.

"There's another way to look at it. Every barrier you add on can drive a group to recruit more people. This is particularly important. The more people who are added to a nuclear conspiracy, the higher chance there is that someone's going to rat it out, that it's going to be exposed through traditional law enforcement and intelligence," Levi says.

Because the technological and security barriers to acquiring radiological materials are so much lower than for nuclear materials, the risk of terrorists setting off a dirty bomb-one made from conventional explosives laced with radiological material-is far greater than the risk of terrorists using a nuclear bomb. Kenneth Luongo, executive director of the Partnership for Global Security, warns that the struggle to contain and secure these materials is at the forefront of the 21st century's nuclear challenge.

Millions of devices contain radioactive materials, from smoke detectors to X-ray machines. They are widely used in manufacturing and medicine, in drilling and mining. In the United States alone, more than 21,000 entities hold licenses to use radioactive materials.

"Even a small amount of radiological material, when packaged with an explosive, could have devastating effects," Luongo says. Radiological dispersal devices, or dirty bombs, "are commonly referred to as weapons of mass disruption because they would likely create major societal upheaval and panic affecting commercial activities, schools and municipal services."

But it's also easy to overstate the vulnerability to and effects of a dirty bomb, others say, a position perhaps best articulated by the late Ed McGaffigan, the longest-serving NRC commissioner, who died last September after a long battle with cancer.

"I personally think that this psychological fear that we have is a combination of threat inflation on the part of the terrorists' capabilities combined with lack of knowledge of real radiation effects," McGaffigan told the Senate Homeland Security Committee's permanent subcommittee on investigations last summer after the GAO sting operation uncovered weaknesses in the agency's licensing process. He said it is unrealistic to think that any country in the world could monitor all radiological materials. While hundreds of devices containing radiological material are lost every year, the quantities are not relevant, he said.

"We should not aid and abet terrorists by fearing things that are the equivalent of working in the Capitol," he said, referring to the fact that the granite used in construction of the U.S. Capitol and Library of Congress emits radiation, something he discovered after mapping the building when his son worked for Sen. John Warner, R-Va., in early 2001.

"The fact is that in the last 11 years that I've been with the commission, the only high-risk sources that have ever been lost are devices used in oil and gas exploration, using iridium-192, a radionuclide that has a relatively short half-life of 73 days. The number of those lost and not recovered is a handful. Sometimes they are lost in the Gulf of Mexico, sometimes in deep waters, and they are very hard to recover," he said.

The devices GAO attempted to obtain in its sting operation-moisture density gauges that contain americium and are commonly used in construction-should not be readily available to anyone for the asking, McGaffigan said. After GAO's experience, he added, the agency changed its licensing process and revised its guidance to suppliers of radiological materials. But McGaffigan stressed that "getting this material doesn't get you an effective dirty bomb." Because the americium is encapsulated in two layers to prevent human exposure, a would-be bomb maker would first have to get at the americium and use it to build a bomb without hurting himself.

"We hear a lot that we have to succeed every time, while the terrorists only need to succeed only once," Levi says. "But if you dig into it, the terrorist group has to succeed [at every point in a multistep process]; we have to succeed only once."

Instead of talking about "layered defense," as Homeland Security officials and experts do, they need to talk about defense as a system, Levi says. "What matters with a layered defense is how and whether any piece of a defense stops a terrorist plan," he says. "What it doesn't look at is how any part of the defense alters a terrorist plot, even if it fails to stop it."

As Levi writes in his book: "Nuclear terrorism is a genuine possibility, but its complexity expands the universe of ways for preventing it."

Cause for Concern

Dozens of radioactive materials are used in medical devices and therapies, industrial applications and academic research. Argonne National Laboratory identified the nine most likely to be used in a dirty bomb. They are:

Sources: Argonne National Laboratory; Centers for Disease Control and Prevention