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may well be the driving factors in Ukraine's ultimate decision, but that decision could be affected by measures that ensure that weapons and fissile materials transferred to Russia will not be reused for military purposes, and that provide compensation for these materials.
Breakdown of the elaborate system of control of nuclear weapons and fissile materials in the former Soviet Union remains a possibility, despite Russian efforts to maintain the former Soviet systems for this purpose. The thefts of conventional weapons and nuclear materials other than plutonium and HEU that have already occurred are disturbing. Enhanced assistance in improving security and accounting for fissile materials in the former Soviet Union is a potentially high-leverage area deserving urgent attention. The broad regime of accounting we recommend could provide an important basis for additional steps to improve security of these materials.
Breakout seems unlikely in the near term. The significant nuclear arsenals that each side will retain under START II will further reduce any motivation that a future Russian government might have for taking such a step. Ratification and implementation of START I and START II are not yet assured, however. The steps that we outline would reduce the potential for breakout, and provide a foundation for deeper reductions and for the inclusion of additional parties in the future.
The foundation of the nuclear nonproliferation regime is the Non-Prolif-eration Treaty (NPT), which is up for extension in 1995. Agreements for secure, safeguarded management and disposition of fissile materials from surplus nuclear weapons could help make clear that the nuclear powers are fulfilling their disarmament obligations under Article VI of the NPT. Moreover, acceptance by the major nuclear powers of safeguards and constraints on substantial portions of their nuclear programs would help to reduce the inherently discriminatory nature of the nonproliferation regime. These steps, while probably not dissuading all nations that might be attempting to acquire nuclear weapons, would help build global political support for indefinite extension of the NPT and strengthening the regime, which are major U.S. policy goals.
International efforts to reduce the proliferation risks posed by the existence of civilian plutonium and enriched uranium rest on safeguards, which are national and international measures designed to detect diversion of materials and enable a timely response, and security, which consists of (currently national) measures designed to prevent theft of materials through the use of barriers, guards, and the like. Standards for both vary widely. Those applied to civilian materials, even separated plutonium and HEU, are less stringent than those applied to nuclear weapons and fissile material in military stocks. Varying and lower standards may be justified in the case of spent fuel for the first decades outside the reactor, when its high radioactivity makes it difficult to steal or divert, but they are not justified in the case of separated civilian plutonium orts such as this.