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have joined in a number of efforts to reduce the danger posed by the enormous quantity of weapons-usable material withdrawn from nuclear weapons.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.
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other nations of the world have joined the treaty as “Non-Nuclear Weapons States,” but one country (North Korea) has withdrawn.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.