Nuclear Nonproliferation: The Role of Complementary Regimes

The Nuclear Nonproliferation Treaty (NPT) is commonly perceived as dealing primarily with horizontal proliferation: this is where it has the most detailed provisions and is the area of greatest achievement—the IAEA’s comprehensive safeguards system. However, the NPT also deals with vertical proliferation—all parties are to pursue effective measures relating to cessation of the nuclear arms race and to nuclear disarmament. Nuclear disarmament will not be possible without supporting regimes and confidence- building measures. This is recognized by the NPT—parties commit not only to nuclear disarmament, but to pursue “a treaty on general and complete disarmament under strict and effective international control.” The form the latter treaty or treaties might t a ke, though clearly relevant to the achievement of NPT objectives, is beyond the scope of this paper, which focuses on nuclear-related regimes. One important complementary regime is the proposed Fissile Material Cut-off Treaty (FMCT). The FMCT wo u l d be a major step in containing vertical proliferation and would bring the three threshold states into the nuclear arms control process. Another important complementary regime is the Comprehensive Nuclear Test Ban Treaty (CTBT), which has benefits in terms of both vertical and horizontal nonproliferation. Horizontal and vertical proliferation are two sides of the same coin: effective containment of horizontal proliferation is an essential precondition for nuclear disarmament—but lack of real progress on disarmament could over time erode the norm against horizontal proliferation. Hence, furthering the conditions needed for nuclear arms reductions and eve ntual disarmament must be a priority—including resolving the considerable verification challenges involved.