Some opponents of nuclear energy cite concerns that civil nuclear power programmes facilitate development - proliferation - of nuclear weapons by states that do not currently possess such weapons.
Historically the states which first developed nuclear weapons - the USA, USSR, Britain, France and China - all did so before developing civil nuclear power plants. These states, sometimes referred to as the nuclear "club", are permitted to keep their weapons under the 1970 United Nations Non-Proliferation Treaty, whilst other states which have signed up to the NPT agree not to develop nuclear weapons. Three states - India, Pakistan and North Korea - have publicly, and Israel has covertly developed nuclear weapons and have not signed the NPT. A dozen or more states had weapons programmes but have since abandoned them (voluntarily or forcibly).
Under the NPT any country wanting to employ civil nuclear power - including research reactors - has to allow inspections of its reactors and storage sites for nuclear materials by the International Atomic Energy Agency, and this protocol has resulted in the detection of attempts to develop weapons programmes such as in Iran and North Korea.
Highly explosive nuclear weapons (as opposed to "dirty bombs") require either highly enriched Uranium or Plutonium, and acquisition of either material is the major challenge in building such weapons. Enriching Uranium requires, in practice, large arrays of centrifuges: this was the technology employed by Iran in its abortive attempt to develop its own bomb. Suitable Plutonium can be produced in Uranium-fuelled reactors by removing the fuel after a short period - a few weeks or months, rather than years - and processing it to extract the Plutonium. Most commercial power reactors run under high pressures and the reactor has to be shut down and depressurised. Unusually frequent stopping and starting of such reactors is obvious to international observers. Plutonium for military purposes is more conveniently produced in reactors where fuel rods can be removed and replaced during routine operation, such as the UK's original Magnox and the USSR's RBMK reactors, and North Korea's "Experimental Power Reactor".
- The conventional wisdom suggests that states with nuclear energy programs are more likely to seek or acquire nuclear weapons. Yet there is a dearth of systematic empirical work that directly assesses this proposition. A systematic analysis of the historical evidence suggests that the link between nuclear energy programs and proliferation is overstated. Although such programs increase the technical capacity of a state to build nuclear weapons, they have important countervailing political effects that limit the odds of proliferation. Specifically, nuclear energy programs increase the likelihood that parallel nuclear weapons programs will be detected and face counterproliferation pressures; they also increase the costliness of nonproliferation sanctions. Contrary to the conventional wisdom, states with nuclear energy programs historically have not been significantly more likely to seek or acquire nuclear weapons. A combination of qualitative and quantitative evidence supports the plausibility of the countervailing political effects of nuclear energy programs
A summary of Miller's paper on the AAAS' Eurekalert news site explains that
- nuclear energy programs do provide an increased technical ability to develop nuclear weapons. However, countries with nuclear energy programs face political obstacles that help counter this proliferation risk, including improved intelligence by outside actors, and the prospect of costly nonproliferation sanctions, which jeopardize the international trade and supplies required for most energy programs to operate. When a country announces plans to develop nuclear energy, this provides an open signal for foreign intelligence agencies to pay closer attention. As nuclear energy programs become operational, the procurement of technology and materials from foreign firms provide these same agencies with opportunities for surveillance, increasing the likelihood that suspicious activities are detected in a timely fashion. Furthermore, given that the nuclear power plant industry relies on a small number of global suppliers, nearly all of whom require International Atomic Energy Agency safeguards and the peaceful use of exported materials, countries with energy programs are generally wary of risking disruptions in supply by seeking to develop nuclear weapons.
- Why Nuclear Energy Programs Rarely Lead to Proliferation Nicholas L. Miller; International Security; 1 Nov 2017 (paywalled)
- Nuclear energy programs do not increase likelihood of proliferation, Dartmouth study finds Dartmouth College; AAAS Eureka; 6 Nov 2017