It’s…complicated: Some thoughts about nuclear terrorism
Editorial by Dr. Andrew Karam
I was in the US Navy from 1981-1989. The world was a fairly simple place – we knew that a nuclear war between the US and the Soviet Union would likely kill hundreds of millions of people and might well cause civilization to collapse. But we also knew that we could – more or less – count on the Soviets to be rational actors. And because of that, both sides had a degree of confidence that neither would want to be the one to fire the first shot.
I was in the US Navy from 1981-1989. The world was a fairly simple place – we knew that a nuclear war between the US and the Soviet Union would likely kill hundreds of millions of people and might well cause civilization to collapse. But we also knew that we could – more or less – count on the Soviets to be rational actors. And because of that, both sides had a degree of confidence that neither would want to be the one to fire the first shot. Things are different now. Instead of the relatively stable world of Mutually Assured Destruction between powers who could (more or less) be counted on to act in their own best interests, we now have a new nuclear power that seems more or less rational but has a potentially irrational foe, a nation that seems irrational (or who might just be an expert manipulator), and one waiting in the wings that might just throw caution and rationality to the winds. And that’s just the nations that have territory and a population to worry about – when we throw in the terrorist groups that are interested in obtaining nuclear weapons things get even more…interesting. It is sort of like adding a meth addict with a gun to a meeting of professional gunfighters.
The thing with nations using nuclear weapons is that they often come with a “return address” of some sort – radar can track missiles and bombers to see where they came from, and even sea-launched missiles are likely to originate from operational areas frequented by the submarines of one nation or another. On top of that, nuclear forensics can help to identify small details about the isotopic makeup of the uranium of plutonium used to make the bomb, and these details can help investigators to figure out what nation made the weapon. And once the origin of the weapon is known, whoever was attacked will know who to retaliate against. That knowledge, thus far, has been sufficient to keep any of the nuclear-armed nations from launching an attack. Even North Korea, with its occasionally wacky leader, has always backed away from the brink.
But what about ISIS or al Qaeda or another terrorist group? Without any territory under their control – and not much (if anything) to lose – what’s to stop them from staging a nuclear attack? And if they have an apocalyptic worldview, then what do they have to lose? That is what makes things so much more complex – and so much more dangerous – than they were during the Cold War.
Luckily making the fuel – the highly enriched uranium and plutonium – for a nuclear weapon is beyond the capabilities of a terrorist group. And without the fuel, there’s no way to make a weapon.
So…terrorists might not be able to make their own fissile materials. But what if they’re able to buy or steal some? Might they even be given some by a sympathizer in a nuclear-capable nation?
Nuclear smuggling is a very real concern that is tracked by Interpol, the International Atomic Energy Agency (IAEA ), and by any number of national security agencies around the world. Materials that could be made into nuclear weapons are usually locked up and heavily guarded, making a daring break-in unlikely. On the other hand, insiders are always a concern – a reluctant insider might be compelled to assist by threatening their family, or a sympathetic insider might simply open the vaults after hours.
If terrorists can get their hands on fissile materials, the next steps are discussed in an interesting article published in the October 2009 issue of Foreign Policy (The Bomb in the Back Yard by Peter Zimmerman and Jeffrey Lewis). In this article, Zimmerman (former Chief Scientist for the Senate Foreign Relations Committee) and Lewis (founder and editor of the Arms Control Wonk blog and a long-standing expert in nuclear non-proliferation) described how a terrorist group might go about doing so. And it’s not only Zimmerman who thinks so. As far back as the 1970s physicist and nuclear weapons scientist Ted Taylor expressed similar concerns in multiple discussions with author John McPhee for his book The Curve of Binding Energy, and more recently Canadian physicist Cameron Reed has also published a number of technical papers that touch on various aspects of this issue. The fact is undeniable – several qualified people think it may happen, making it a possibility we must take seriously.
And there’s another complicating factor to consider – nuclear weapons are hard to detect. Part of the problem is that neither uranium nor plutonium are very intensely radioactive, and much of the radiation they do emit is low-energy and is easily shielded. Neutrons are more penetrating, but uranium doesn’t give off many neutrons and even plutonium has a neutron signature hard to pick up from more than a few tens of meters away1his has been the subject of several papers by several non-proliferation scientists, including Steve Fetter, who was able to make direct measurements of some Soviet nuclear weapons in 1989. ￼Using data collected by Fetter, Rikkyo University Professor Iwao Ogawa calculated the maximum detection distance for weapons using both uranium and plutonium, calculating a maximum detection distance of up to 15 meters for highly enriched uranium and 25 meters for weapons-grade plutonium. Using more specialized detectors, Ogawa calculated a maximum detection distance of up to 40 meters using a counting time of one minute and 100 meters with a longer – one hour – counting time.
A detection distance of 100 meters sounds fairly promising until we think it through. During an aerial survey, a fixed-wing airplane can’t hover at all, and a helicopter can’t hover for an extended period of time without attracting attention. Not only that, but it is hard to survey an entire city on a 100-meter grid, spending an hour at each grid point. Consider my hometown (Akron, Ohio) is a relatively minor city with fewer than 200,000 residents, with a surface of about 160 square km. Surveying Akron on a 100-meter grid would require over 12,000 survey points and take over 12,000 survey hours to perform – this is about 18 months using a single helicopter. Performing a nuclear interdiction survey using vehicle-mounted instruments is equally challenging. So, putting all this together:
- The world is politically a more complicated place with more nuclear weapons states than was the case in the past.
- There have been – and likely will continue to be – opportunities for non-state actors to obtain fissile materials.
- And once they have them it is possible to construct a crude nuclear weapon
- Non-state actors might have greater motivation and fewer compunctions against their use.
The bottom line is that things were much simpler when all we needed to worry about was global thermonuclear devastation.
Andrew Karam is a radiation safety professional with 35 years’ of experience in his profession, beginning with the eight years he spent in Naval nuclear power. During his career Dr. Karam has worked for state and local governments, for an environmental consulting firm, and at two universities. He has a PhD in Environmental Science and is board-certified in health physics.
Dr. Karam has served on two committees of the National Council on Radiation Protection and Measurements and on a committee of the National Academies of Science. He has participated in several international missions on behalf of the International Atomic Energy Agency and, most recently, he travelled to Japan a month after the reactor meltdowns as part of a team that worked with physicians and emergency responders caring for victims exposed to radiation.
Andrew Karam is the author of 16 books and 20 scientific papers as well as 200 encyclopedia articles. He has also written several hundred articles, editorials, and essays for both professional and general audiences. He worked for the NYPD Counterterrorism Division as the Director of Radiological Operations.