Center for Strategic Decision Research


Today’s Nuclear Concerns: Dirty Bombs, Improvised Low-Yield Nuclear Devices, and Modern Weapons: Why the World Needs to Come Together

The Honorable Dale Klein
U.S. Assistant to the Secretary of Defense for Nuclear, Chemical, and Biological Defense Programs

The Hon Dale Klein
"My message regarding [the] threat is simple but sobering: the possibility that a clandestine nuclear attack will occur somewhere in the world is real, serious, and present."


As the U.S. Assistant to the Secretary of Defense for Nuclear, Chemical, and Biological Defense Programs, it is my responsibility to understand a particularly frightening threat facing the United States and the world– a clandestine nuclear attack, which can be defined as any attack involving a nuclear weapon, improvised nuclear device (IND), or radiological dispersal device (RDD) delivered by unconventional means, not by military missile or aircraft. 

My message regarding that threat is simple but sobering: the possibility that a clandestine nuclear attack will occur somewhere in the world is real, serious, and present. At issue is whether we, as a global community, believe that the threat is real enough, serious enough, and present enough to warrant our coming together to combat its danger. Also at issue is the question of whether we believe there is anything we can do about the danger of such an attack even if we work cooperatively and take collaborative action. 

My response to each of those questions is an emphatic yes—the threat is real enough, serious enough, and present enough to demand immediate action, and, yes, if the global community can come together to fight those who would perpetrate such violence against us, I believe that our efforts can make a real difference. 

Before I discuss this threat in more detail, I would like to point out some positive action that has already been taken. It is my opinion that the NATO nuclear umbrella agreement has prevented more countries from developing nuclear weapons than all the treaties we have developed. Many, if not all, of the original NATO countries had the technical and financial ability to design and build a nuclear weapon. However, by participating in the NATO agreement, the need to do so, both perceived and real, was reduced. 

There are no similar agreements in the Middle East and other regions. Therefore, we have seen the desire of several countries, including Iran, Iraq, Libya, Pakistan, India, and North Korea, to develop nuclear weapons. In fact, since the end of the Cold War the number of countries that possess the knowledge, materials, and technical capability to produce nuclear weapons has nearly doubled.


First, let’s consider the demand side of the nuclear proliferation problem. I think we can safely say that demand is up—states are seeking to develop and acquire nuclear weapons for many reasons, including military, political, and economic. The director of the U.S. Central Intelligence Agency recently commented that, “The desire for nuclear weapons is on the upsurge. Additional countries may decide to seek nuclear weapons as it becomes clear their neighbors and regional rivals are already doing so. The domino theory of the twenty-first century may well be nuclear.” (George Tenet, Feb. 11, 2004) In addition, rogue states and substate groups seem to be motivated by the destructive potential of these weapons or devices as well as the desire to achieve the psychological impact an attack by such means would engender. 

It seems likely that the demand for nuclear weapons is not going to decline in the coming years. So let us now take a look at the supply side of the problem. 

The knowledge, technology, and materials required to implement a successful clandestine nuclear attack are spreading at an accelerated rate to both state and nonstate actors. The most difficult obstacle now facing a terrorist is acquiring fissile material to use in a weapon or an improvised nuclear device. While states have traditionally sought to produce plutonium or highly enriched uranium themselves, there is a dangerous potential for procuring it on the black market as well as stealing it from poorly secured areas. Because the Cold War ended, surplus nuclear assets exist, including people, technology, facilities, and materials. 

The former Soviet Union’s transition from a secret military infrastructure to a commercial enterprise raises issues today related to safety, security, and the prevention of the proliferation of weapons of mass destruction. Several countries are currently providing financial and technical assistance to Russia to help secure its nuclear weapons and usable weapon material. Previous methods of controlling proliferation, designed to limit trade where necessary and prevent the diversion of civilian material, will not work, either in Russia or in Iran, where this issue is also a concern, because of the co-mingling of defense and civilian infrastructures and materials. The global community must instead find better ways to prevent diversion, ensure transparency, and assure the irreversibility of this dual-use process. 

Similar issues have also arisen concerning other nations that are part of the burgeoning nuclear suppliers network. Over the last 20 years, several developed and underdeveloped countries have slowly weaned themselves from any need for foreign support, goods, and services and have emerged as a nascent suppliers group that will be able to provide competitive cradle-to-grave nuclear energy services throughout the world for the next 10 to 20 years. These are the suppliers that will provide nuclear goods and services to support third-world industrialization and the global energy demand. And as this emergent suppliers club expands its membership, so too will the number of targets for ambitious proliferators increase. 

By 1996, 15 countries had developed complete and indigenous nuclear-fuel-cycle capabilities. Some of these countries, including Japan, China, South Korea, Argentina, India, and Brazil, now stand poised to become very competitive nuclear suppliers to the next growth area. Some have already established an independent multilateral cooperative network. 

Weapons-grade material, moreover, is not necessary to produce a radiological dispersal device, which is designed to disperse radioactive material and thereby cause destruction, contamination, and injury—a “dirty bomb.” However, acquiring such material through theft or illegal commerce is less difficult than obtaining material for a nuclear weapon or improvised nuclear device.  

Abdul Qadeer Khan, the father of Pakistan’s nuclear program, has already demonstrated a large and potentially enormous appetite for nuclear materials, technologies, and expertise. Because of his public role, he was well positioned to succeed in his other, more covert role: as a prominent black marketer of nuclear materials and knowledge to state regimes and, perhaps more indirectly, to sub-state terrorist groups determined to acquire a nuclear capability to further their horrific schemes. 

But in addition to Khan’s work selling instruments of terror and destruction, he also helped to create menacing networks that persist though his occupation as an arms dealer has ended. Khan became quite wealthy selling Pakistan’s nuclear technology, but his significant and frightening success resulted from a simple economic formula: demand creates supply. It is going to take great effort to reduce the demand as well as eliminate, or at least reduce, the supply. 


The consequences of a clandestine nuclear attack would be enormous. While there are a number of unconventional weapons that fall under the category of weapons of mass destruction, only nuclear weapons truly fit that bill. Only nuclear weapons have the destructive potential to threaten both the physical integrity and the physical existence of states. 

But what about “weapons of mass disruption?” RDDs—dirty bombs—would not achieve mass destruction, certainly. But an RDD has the potential to cause significant damage and injury if set off in a heavily populated area. The same holds true for an IND. And make no mistake, a terrorist capable of obtaining the materials for such a device would most certainly use it. As demonstrated on September 11, 2001, and more recently in Spain, terrorists do not differentiate between those in uniform and innocent civilians. They have demonstrated a clear disregard for human life. 

But should the consequences of a clandestine nuclear attack be measured only in terms of lives lost and economic cost? Or should we also consider the consequences associated with the regional, national, and potentially global trauma that would follow such an event? A clandestine nuclear attack would have repercussions that could profoundly impact the world politically, economically, and even culturally in a variety of ways. 

Any clandestine nuclear attack—whether it results in tremendous physical damage and heavy fatalities or a relatively small amount of physical destruction—will be transforming in ways on which we can only speculate. But let us speculate for a moment. An entire global generation of men, women, and children might be permanently scarred by such a life-altering event. Time itself would be measured in terms of before and after, similar to the way the phrase “after 9-11” has permeated the American idiom. No one alive at the time of such an attack—anywhere in the world—might ever feel safe and secure in the same way that they had before; many might never feel truly safe again. An enormous number of people could become intimately familiar with fear and possibly motivated by fear. Thus the threat is serious. 


Do we really believe the threat exists today? And is it high? Or can we afford to delay acting? To answer these questions we must look at the issue of secondary supply, which has emerged as a growing concern in recent years. 

As their domestic nuclear capabilities have improved, nations that traditionally have been recipients of nuclear-related technology and materials are themselves becoming suppliers of those same technologies and materials. Pakistan is a prime example of this phenomenon, although Iran and North Korea are also cause for concern. In fact, North Korea has resumed its production of plutonium, and information provided by Abdul Quadeer Khan confirms the country’s efforts to develop highly enriched uranium. Coupled with its withdrawal from the Nuclear Proliferation Treaty and its nuclear weapons capabilities, there is justified concern that North Korea could sell plutonium or other nuclear weapons–related material and technology to other sub-state groups. 

So how much longer can we, the global community, wait to take action against the increasing proliferation of nuclear weapons? It would appear that the time for action is upon us. The threat is present. 


If we accept that the problem is real, serious, and present, we must next ask a difficult and controversial question: Is there a solution? The answer to that question is yes. Can we eliminate the threat? That answer is no. But can we mitigate the threat? A definite yes. 

There are three actions we can take to reduce the danger associated with the threat of a clandestine nuclear attack:

  • Clearly our top priority must be the establishment of treaties and agreements that provide for real consequences in cases of noncompliance; harsh words by the IAEA when North Korea kicked them out or when Iran stalls on meeting the additional protocol requirements have little real impact. Simply put, without the support of real action in the face of national defiance, global treaties carry little weight. Agencies such as the IAEA become subject to the whims of dictators who clearly recognize their lack of authority. If treaties and agreements are to be effective, then they must be supported by UN resolutions that are enforced—not crippled by indecision and inaction or more resolutions. The wrong message is consistently being sent and the result continues to be the capability to proliferate weapons of mass destruction. 
  • Develop a better accounting system for all nuclear material. 
  • Develop a global monitoring system to track the movement of nuclear material. 

Such detection and neutralization efforts will help to create uncertainty in the minds of those who want to do us harm, and increased uncertainty will result in a decreased likelihood of attack. We must exploit our adversaries’ fear of failure. 

The best way for us to prevent a clandestine nuclear attack is to come together, work together, and succeed together. We must help each other in order to help ourselves. To do this we must take a multilayered approach to the problem, including efforts to:

  • Prevent proliferation
  • Deter the use of nuclear or radiological weapons and devices 
  • Defend against such use
  • Defeat those who would employ such means.


The threat of a clandestine nuclear attack—using nuclear weapons, improvised nuclear devices, or RDDs– is real. Therefore we must all work together to build the relationships that will allow us to cooperate and collaborate to meet this challenge, and realize that an attack on any one of us is an attack on all of us. The September 11 terrorist attack in the U.S. was felt by citizens of all nations. Similarly, few in the world could claim to be immune from the fear generated by the deadly sarin gas attack in Japan in 1995, or the discovery of the lethal agent ricin in London in 2003, or the anthrax attacks in the United States in 2001. While we tend to become less concerned about such events as time passes, I believe a clandestine nuclear attack would have a negative impact over a much longer period of time. 

Presently we have a new–but perishable–opportunity to share management of past, present, and future nuclear stresses through visionary leadership. But we need international cooperation and collaboration on a scale never before achieved—which is, I believe, possible. We all have a common enemy, terrorism, and a common goal, peace and prosperity. So together, I believe we can develop an imaginative new world blueprint for preventing the further proliferation of nuclear materials and technologies, deter potential adversaries from even attempting to attack using clandestine nuclear weapons and devices, defend ourselves against such attacks, and defeat decisively those who would effect such atrocities. With enough cooperation, we may even be able to eradicate the underlying seeds of terrorism and provide the basis for a millennium of world peace and prosperity.


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