Though a massive attack with a full-fledged nuclear weapon is highly unlikely, a so-called "dirty bomb" scenario is not out of the question.
PARIS — The Islamic State (ISIS) wants us to believe that terrorists will soon be equipped with nuclear weapons. Authorites in Washington, where a recent series of four summits on nuclear security was held, have expressed concern about the Syrian-Iraqi situation. And Western intelligence services know that jihadists have been trying to lay their hands on radioactive material.
There is, however, no serious precedent of nuclear terrorism. In 1995, in a Moscow park, Chechen rebels planted an unactivated device containing dynamite and caesium. In 1998, near Grozny, other Chechens made a bomb containing unidentified radioactive substances. In 2003, British intelligence services found evidence suggesting that al-Qaeda, in Afghanistan, was able to produce a small dirty bomb, but no such device was ever found.
Faced with this threat, experts advise common sense. They dismiss, for example, the possibility of terrorists capturing an existing nuclear missile, given how complex the access and the use of these weapons are. Nor do they believe that terrorist groups can manufacture a military-grade weapon — not without support of a state.
"If you're the glass-half-full type, you can take some solace in knowing that the most dire scenario is also the least probable," writes Elisabeth Eaves, a colunmist for the Bulletin of the Atomic Scientists.
But what about an attack on a power station? "That risk is real," U.S. specialists Graham Allison and William Tobey wrote in an April op-ed piece published by The New York Times. Such an attack "wouldn't set off a mushroom cloud or kill hundreds of thousands of people," they explained. "But it would spew large amounts of radiation, spark a mass panic and render vast swaths of land uninhabitable."
An even more credible threat, experts warn, is a so-called dirty bomb, made of radioactive components used in civilian contexts. The device would combine explosives and material collected from research reactors, medical facilities or industrial plants.
"This is one of the biggest concerns, even if the ultimate probability of use is very low," says Benjamin Hautecouverture, a researcher at the Foundation for Strategic Research, a Paris-based think tank. If such an attack did occur, "It would mostly lead to a panic reaction, in a limited area, and not to mass destruction," he adds. "Human damage would be less significant than what Kalachnikovs or a conventional bomb could do."
The International Atomic Energy Agency (IAEA) keeps a close watch on any incident, criminal or otherwise, related to the handling or transport of radioactive material. The list is alarming in its length: 2,734 cases noted between 1993 and 2014. Of those, however, only 442 are considered criminal acts involving illegal possession or suspicious movements in preparation for trafficking nuclear and radioactive matter. Truly troubling cases, involving highly enriched uranium (13 incidents) or plutonium (three incidents), for example, were fewer still.
Experts believe this type of trafficking isn't driven so much by organized demand as it is by supply-side interests. Such cases, in other words, involve individuals trying to cash in on their privileged access to radioactive material.
The other thing to keep in mind is the quantity involved in these cases. While a few incidents involved seizures of kilogram quantities of potentially weapons-grade nuclear material, according to the IAEA, most involved far smaller amounts — not enough, in other words, for effective use as a weapon component. "Great quantities are required to efficiently disperse radioactive matter through explosion," notes Hautecouverture.
In reality, say experts, dozens of kilograms would be needed — much more than the "apple-sized" amount that President Barack Obama made in remarks made recently in Washington. "The smallest quantity of plutonium — about the size of an apple —could kill and injure hundreds of thousands of innocent individuals."
Since the collapse of the Soviet bloc, states have remained very alert to the nuclear threat, and made concerted efforts to reduce the risk. Russia and the U.S. have taken a number of initiatives aimed at preventing nuclear terrorism. France has also made decisions accordingly, repatriating research reactors, for example, from places like Kinshasa, in the Democratic Republic of Congo, and Cocody, in Ivory Coast.
At last month's summit in Washington, Obama said global efforts to improve nuclear security have removed from circulation material that is equivalent to 150 nuclear weapons, safeguarding it from extremists. "That's material that will never fall into the hands of terrorists," he said.
The most fearsome impact of a dirty bomb, say experts, would be its economic costs — cleaning of an area, neutralization of a vital installation — and psychological toll. Will that alone be enough to motivate terrorist groups given their demonstrated interest in sowing fear through high-profile displays of violence? That is precisely the question political leaders, desperate not to be caught off guard, are grappling with right now.