Nuclear Proliferation Risks, New and Old
During the past decade, the United States and Russia have joined in a number of efforts to reduce the danger posed by the enormous quantity of weapons-usable material withdrawn from nuclear weapons. Other countries and various private groups have assisted in this task. But many impediments have prevented effective results, and most of the dangers still remain. Even more troubling, this threat is only one of several risks imposed on humanity by the existence of nuclear weapons.
These risks fall into three classes: the risk that some fraction, be it large or small, of the inventories of nuclear weapons held by eight countries will be detonated either by accident or deliberately; the risk that nuclear weapons technology will diffuse to additional nations; and the risk that nuclear weapons will reach the hands of terrorist individuals or groups.
The United States has undertaken diverse programs to reduce these risks. But efforts have been slow and irregular, and the priorities in addressing these problems have been distorted by politics.
Indeed, success in containing these risks would fly in the face of historical precedent. All new technologies have become dual-use, in that they have been used both to improve the human condition and as tools in military conflict. Moreover, all new technologies have, in time, spread around the globe. But this precedent must be broken with respect to the release of nuclear technology.
Risk is the product of the likelihood of an adverse event multiplied by the consequences of that event. Since the end of the Cold War, the likelihood that one or another country would deliberately use nuclear weapons has indeed lessened, although the consequences of such use would be enormous. Therefore, this risk has by no means disappeared. In particular, nuclear weapons might be used in a regional conflict, such as between India and Pakistan.
The risk of proliferation of nuclear weapons among countries has been limited in the past by the Nuclear Non-Proliferation Treaty (NPT), signed in 1968. The treaty recognizes five countries as "Nuclear Weapons States," and three other countries not party to the treaty are de facto possessors of nuclear weapons. All other nations of the world have joined the treaty as "Non-Nuclear Weapons States," but one country (North Korea) has withdrawn. Some countries--presumed to include Iran and, until the ouster of Saddam Hussein, Iraq--maintain ambitions to gain nuclear weapons. A much larger number of countries have pursued nuclear weapons programs in the past but have been persuaded to abandon them.
The NPT is a complex bargain that discriminates between have and have-not countries. The have-not nations have agreed not to receive nuclear weapons, their components, or relevant information, whereas the Nuclear Weapons States have agreed not to furnish these items. In order to decrease the discriminatory nature of the agreement, the nations possessing nuclear weapons are obligated to assist other nations in the peaceful applications of nuclear energy. And, most important of all, the Nuclear Weapons States have agreed to reduce the role of nuclear weapons in international relations and to work in good faith toward their elimination. It is in respect to this latter obligation that the United States has been most deficient. In fact, the current Bush administration's recent Nuclear Posture Review projects an indefinite need for many thousands of nuclear weapons, and even searches for new missions for them.
The risk posed by the possible acquisition of nuclear weapons by terrorists is growing rapidly. Deterrence prevented direct military conflict between the United States and the former Soviet Union for many years, and deterrence retains its leverage even over the so-called "states of concern," such as North Korea. But deterrence will not restrain terrorists driven by fanatical beliefs. Therefore, the prevention of nuclear catastrophe caused by terrorists has to rely either on interdicting the explosive materials that are essential to making nuclear weapons (highly enriched uranium and plutonium, in particular) or on preventing the hostile delivery of such weapons.
Once a terrorist group acquires nuclear weapons, preventing their detonation on U.S. soil would be extremely difficult. Such weapons might be delivered by aircraft or cruise missile, or they might be detonated on board ships near U.S. harbors. As demonstrated by the leakage of illegal drugs into the United States, closing U.S. boundaries to the entry of nuclear weapons is essentially impossible.
Against this multitude of delivery methods, the enormous effort that the United States spends on ballistic missile defense is an inexcusable distortion of priorities. Indeed, it is extremely unlikely that terrorists would ever gain access to ballistic missiles. The first line of defense against nuclear terrorism must be safeguarding the vast worldwide stockpiles of nuclear weapons-usable materials. Those inventories are sufficient to produce more than 100,000 nuclear weapons. According to public sources, small shipments containing a total of roughly 40 kilograms of smuggled nuclear explosive material have been seized worldwide between 1992 and 2002, generally originating in Russia.
Although public agencies and private groups in the United States have been working with Russia to improve "materials protection control and accounting" of its dangerous materials, actual achievements have been moderate. Several thousand Russian participants have received training in control and accounting techniques, and the nation has developed a number of federal regulations covering such activities. Still, controls over only about one-sixth of Russian nuclear explosive materials have been upgraded to standards comparable to those in the United States. And work to interdict nuclear smuggling at key Russian border crossings is only about 15 percent complete.
A deadly combination of U.S. and Russian travel and access restrictions is preventing truly effective collaboration and causing major delays. Russian security services continue to be preoccupied with preserving the secrecy of the nation's nuclear weapons facilities, whereas the U.S. Department of Energy has been insisting on direct access by its personnel in order to ensure that U.S. funds are being properly spent in reducing risks. There also is the matter of whether Russia can achieve sustainability for its program to safeguard nuclear materials. Foreign assistance is necessary to initiate action, but sustainability has to be the responsibility of the Russians themselves.
The risks posed by nuclear weapons are perhaps the most threatening results of the interaction of science and technology with human endeavors. Can humanity successfully prevent these new technological developments from concentrating enormous destructive power in the hands of an ever-smaller number of individuals? The answer to this question remains open. The United States has the most to lose if nuclear weapons fall into the hands of terrorists, but thus far the nation has failed to take constructive leadership in attacking that risk.
Wolfgang K. H. Panofsky (firstname.lastname@example.org) is director emeritus of the Stanford Linear Accelerator Center at Stanford University.