Editor's Note: This is the third in a series of analyses on the feasibility and relevance of nuclear weapons in the 21st century. Since Sept. 11, 2001, one can hardly discuss nuclear weapons in the 21st century without also talking about terrorism. Yet STRATFOR has deliberately left this aspect of the nuclear dynamic until later in our series on the subject because, while we do not categorically rule it out, we also do not view the use of nuclear weapons by terrorists or other nonstate actors as a likely threat. As a class, chemical, biological, radiological and nuclear (CBRN) weapons present significant challenges for development — challenges compounded by considerations unique to nonstate actors. STRATFOR has repeatedly pointed out that chemical and biological weapons are expensive, are difficult to use and have proven to be largely ineffective in real-world applications. A comparison of the ineffectiveness of the Aum Shinrikyo chemical and biological attacks in Tokyo with the effectiveness of the March 2004 jihadist attacks in Madrid clearly demonstrates that explosives, pound for pound, are far cheaper, easier to use and ultimately more efficient at killing people. The failure by jihadists in Iraq to use chlorine effectively in their attacks also underscores the problem of effectively using improvised chemical weapons. These cases are also illustrative of why CBRN weapons are not necessarily "weapons of mass destruction" (WMD). There is an important and stark distinction between these two terms, which are too often viewed as synonymous. The former, CBRN, is a class of devices and weapons that are used to inflict harm. The latter, WMD, is a measure of potential lethality. The anthrax attacks in the United States in the wake of 9/11 used a CBRN agent but could hardly have been classified as attacks utilizing WMD. The same is true of radiological weapons. Only nuclear devices and weapons — if they are designed properly and sufficiently fueled — are categorically WMD. Even the most rudimentary device could potentially devastate the heart of a major urban area. Perhaps the most important lesson of 9/11 for nonstate actors was that methods of attack that are less difficult to develop and execute than nuclear attacks (such as using large, fully fueled commercial airliners as guided missiles) can achieve WMD results. Though a nuclear or radiological attack is certainly an attractive prospect for groups like al Qaeda, the ability of nonstate actors to actually develop or acquire the means to undertake such an attack is an essential consideration in evaluating the threat.

Radiological Dispersal Devices

A radiological dispersal device (RDD), also called a "dirty bomb," is simply a device that disperses radiation. Depending on the motives of those planning the attack, such a device could be a low-key weapon that surreptitiously releases aerosolized radioactive material, dumps out a finely powdered radioactive material or dissolves a radioactive material in water. Such methods would be intended to slowly expose as many people as possible to the radiation. Alternatively, even a low-tech improvised explosive device could hypothetically be used to disperse a radiological isotope (though it may not be the most efficient means — and the explosive itself may be the most lethal part of the entire apparatus). However, unless large amounts of a very strong radioactive material are used, the effects of such an exposure are more likely to be long-term rather than sudden and dramatic: people dying of cancer years later rather than acute radiation poisoning at the time of the attack. Radioisotopes appropriate for such devices — even the most dangerous — have legitimate medical, commercial and industrial uses. The International Atomic Energy Agency has warned that such radioisotopes are readily available to virtually any country in the world — and they are almost certainly not beyond the reach of even moderately capable nonstate actors. And they can be deadly. In 1987, in Goiania, Brazil, a tiny radiotherapy capsule of cesium chloride salt was accidentally broken open, resulting in four deaths due to sustained exposure and $20 million in damages and cleanup costs. But the RDD is really a contradiction in terms. Maximizing the harmful effects of radiation involves maximizing exposure to the highest possible concentration of the radioisotope. By dispersing the radioisotope, the RDD necessarily dilutes its effectiveness. Meanwhile, the use of an explosion to disperse the radioisotope alerts the intended victims, who evacuate the area. Radioisotopes have been more effectively used in radiological emitting devices (REDs) during targeted assassinations. A deadly radioisotope is concealed, for example, in a victim's office, where the sustained exposure over the course of days and weeks causes lethal effects. REDs are even less complex, and it is somewhat surprising that one has yet to be used in Europe or the United States. On the other end of the spectrum from the Goiania accident is the 1986 Chernobyl nuclear disaster in northern Ukraine, when a 1-gigawatt power reactor exploded. It is estimated that more than one hundred times the radiation of the Hiroshima bomb was released — the equivalent of 50 million to 250 million grams of radium. More than 40 different radioisotopes were released, and there was a measurable rise in Cesium-137 levels across the entire European continent. No RDD could aspire to anything close to such effect. Chernobyl wrought untold suffering, and estimates suggest that it may one day ultimately contribute to the deaths of 9,000 people. But many of those are still alive today, more than 20 years later. While STRATFOR by no means seeks to downplay the tragic consequences of this disaster, consider the numbers: 31 people died in the explosion and immediate aftermath. Today, 5.5 million people live in the contaminated zone — many of those within or nearly within the specified European Union's dosage limits for those living near operational nuclear power plants. The most strategic consequence of this sort of destruction is economic. The Chernobyl disaster ultimately cost well in excess of $100 billion. As far as RDDs are concerned, STRATFOR has long characterized them as weapons of mass disruption. The concept has seen much wider discussion following 9/11. And, given the ubiquity of radioisotopes in modern society, effective security surrounding all radioisotopes is not likely. The RDD threat is a reality of the 21st century and is impossible to fully defend against. But the impact of an RDD pales in comparison to what even the most crude nuclear device can do.

Nuclear Devices and Weapons

Indeed, the most rudimentary nuclear device can wreak immediate and extensive devastation. The good news is that, unlike RDDs, a nuclear device is neither easily fabricated nor easily acquired. STRATFOR has discussed the challenges facing state actors that want to embark on such a path. A nuclear weapons program represents a profound and comprehensive commitment of national resources, requiring not just a single facility but a complete industrial base. And the challenges are compounded dramatically when the nation-state seeks to hide the pursuit from the international community. It is not a matter of simply recruiting or kidnapping a few experts. A nuclear weapons program requires the long-term ability to establish and maintain facilities — often very electricity-intensive — and conduct years of experimentation. Immense quantities of materials must be acquired from abroad — everything from raw precursors to fissile material to high-grade industrial components — often subject to intense international scrutiny. It took North Korea extensive Soviet assistance with both civilian and military nuclear technology and more than 50 years to get to the point where it could test a device that fizzled. Though subject to international sanctions, Pyongyang was able to accomplish this with facilities that were never bombed and the industrial resources of the entire nation. Ultimately, even nonstate actors that control territory – such as Hezbollah and the Revolutionary Armed Forces of Colombia — are regularly disrupted by opposing state actors and would be stretched to coordinate such an effort (holding hostages for years is not the same as sustaining and powering a complex and fixed nuclear development facility for a decade or more). Given the current state of world affairs, it is simply not possible for a nonstate actor to successfully fabricate a nuclear device from scratch. But that's not the only way to obtain one. The nonstate actor could acquire fissile material or other important ingredients — or even a fully fabricated weapon — from someone else. How difficult is this? The fall of the Berlin Wall in 1989 and resulting demise of the Soviet Union were chaotic, and there are known to have been security issues surrounding the Soviet nuclear arsenal outside Russian borders. There is also the rumored loss of "suitcase nukes" — nuclear weapons the Soviets supposedly designed and built in secret to fit, essentially, into a large suitcase. Suitcase nukes have become something of an urban myth in the world of nuclear weapons security. The reality is this: To be reduced to the size of a suitcase, a nuclear weapon would have to be a very sophisticated, high-maintenance device. Even if such a weapon did exist, and even if the Soviets did manage to lose a few and even if those who acquired them were able to also acquire the codes and procedures necessary to arm the weapons, they would not likely be usable. The idea that such a weapon can be stashed in a cave somewhere for nearly two decades and still be a viable weapon is simply not grounded in fact. Complex warheads have elements such as tritium that have to be replaced from time to time. Depending on the device design and element used (uranium or plutonium), even the core might need to be respun. Moreover, complex electronic components essential to the functioning of such a small weapon are unlikely to work with the requisite precision — if at all — after years of neglect. While the U.S. Air Force has had recent custody problems with nuclear weapons, none posed any real threat that a U.S. weapon would fall into someone else's hands. Even if one did, modern weapons are equipped with numerous (and highly classified) layers of safety features — from permissive-action links to safeties that could render the fissile core difficult to repurpose if it were improperly accessed. Not all nuclear arsenals around the world are equal, of course. The security of Pakistan's arsenal has caused perhaps the greatest concern, but it has been a primary U.S. focus since 9/11. However, as long as Pakistan's military remains intact, so should its nuclear arsenal. It is thought the United States might have shared its expertise with nuclear weapon safeties with Pakistan to help ensure high-level government control. A more pressing concern than obtaining a weapon is obtaining fissile material — specifically, highly enriched uranium that contains at least 80 percent of the isotope Uranium 235 and is usable in a nuclear device (this is called "weapons-grade HEU"). Because Uranium 235 is a particularly safe isotope, weapons-grade HEU can be handled by an unprotected human being. (Plutonium, on the other hand, is less of a concern in terms of a terrorist threat not only because it is far more radioactive and much more toxic but also because even the most crude plutonium device requires implosion to create a supercritical mass, which presents numerous challenges all its own.) A sufficient quantity of weapons-grade HEU (100 pounds, say, although a number of factors would determine the necessary quantity for an effective weapon) could hypothetically be fitted into a crude gun-type device that could propel one mass of HEU into another to create a supercritical mass. Such a device would be grossly inefficient and could possibly, with a high degree of luck, achieve a yield of a few kilotons, much less than the Hiroshima bomb. But fabricating a crude device is one thing; obtaining the necessary HEU is something else altogether. Once the HEU is in hand, the remaining hurdles — at least hypothetically — are far more surmountable for the nonstate actor. Great strides have been made in the last five years in securing HEU stocks, which are mainly in the United States and countries of the former Soviet Union (although HEU is used as nuclear reactor fuel worldwide). It is becoming increasingly unlikely that a meaningful quantity could be acquired by a nonstate actor. Nevertheless, the security of weapons-grade HEU remains the single most important factor in preventing nuclear material from falling into the wrong hands.

Deterrence

While nonstate actors are not likely to overcome the challenges of obtaining or building a nuclear weapon, neither are they likely to be deterred by them. The logic of mutually assured destruction is based on mutual vulnerability — the absolute certainly that the other side can hit you as hard as you hit it. In the case of state actors, those vulnerabilities are entire cities –- immobile and inherently exposed population centers. And while some elements of a nuclear arsenal can be made mobile or deployed at sea, much of the nuclear enterprise is necessarily composed of large, fixed and identifiable installations. Nonstate actors like Hezbollah do have centers of gravity — such as specific neighborhoods in Beirut — but not the same targetable population centers, seats of government and military installations that state actors have. If nuclear weapons failed to deter China from launching a massive assault into North Korea in 1950 despite the U.S. nuclear arsenal, or the Arabs from briefly threatening the heart of Israel in 1973 despite the Israeli arsenal, they would have even less deterrent value to al Qaeda. A 350-kiloton strategic warhead (or a tactical nuke, for that matter) is simply too massive a tool to be relevant against an enemy enmeshed in a civilian population. Indeed, some of the more radical (and apocalyptic) groups such as al Qaeda would like nothing more than to provoke the United States into doing something rash against a civilian population center — perhaps sufficient (in its mind, at least) to unite the Muslim world and give rise to a new caliphate. And though a new generation of nuclear weapons might be better tailored to take out deeply buried cave complexes, terrorists who already see the world ruined by Western influence and are prepared to die for their goals cannot be threatened with death — nuclear or otherwise.

Conclusion

The risk of nuclear attack by terrorists is often clouded in hype and alarmism. A risk assessment grounded in actual capabilities puts the risk in a much clearer light. But regardless of how difficult such an attack would be to mount, it could — if successful — have a devastating impact on the target country's economy and collective psyche. And terrorist groups intending to use a nuclear device are not likely to be discouraged by traditional deterrents. As the international system is stuck with the reality of nuclear weapons, so too is it stuck with the specter of nuclear terrorism. Such a threat — posing low risk yet high consequences — warrants continued international vigilance.