The U.S. and European countries lifted nuclear-related sanctions against Iran on January 16 as part of a deal in which the country agreed to limit its nuclear activities and accept a new system of international inspections. Last week Iranian President Hassan Rouhani was in France, seeking to rekindle long-dormant Western business connections.
The issue now is how the international community can be confident that Iran is not violating the deal, formally referred to as the Joint Comprehensive Plan of Action. A helpful approach is to ask two questions:
- Could Iran collect the nuclear material needed to build a weapon?
- Could the international community discover those efforts before it was too late?
Iran agreed never to develop nuclear weapons when it signed the Nuclear Non-Proliferation Treaty in 1968. There’s no ironclad method to prevent Iran from breaking its promise and developing nuclear weapons, but this new agreement builds in a number of strong protections. In conjunction with U.S. and allied intelligence capabilities, these rules mean even a sophisticated and carefully executed secret plan would carry a high risk of detection.
Three steps of development
There are three major tasks involved in building a nuclear weapon: acquiring the nuclear fuel, constructing the other components of a nuclear bomb or warhead and developing a delivery system.
Given Iran’s history with ballistic missiles, it is best to assume that Iran would have relatively little difficulty developing a suitable delivery system.
A December 2015 report from the International Atomic Energy Agency (IAEA) explored the so-called “possible military dimensions” of Iran’s nuclear program, but Iran’s research and development activities in the field of weaponization remain uncertain. Some of these activities, such as performing computer simulations for weapons design, are fairly easy to hide. Others, like developing high-speed electronic switches, have applications in both nuclear weapons and nonnuclear industries, meaning Iran could conceal military intentions under cover of peaceful work. It is best to assume that Iran would be able to quickly assemble a bomb in a hidden location if it ever acquired enough weapons-usable nuclear fuel.
Consequently, the focus of international effort should be on blocking Iran’s access to nuclear material, and rapidly detecting any clandestine attempts to acquire it.
Making the fuel
There are two basic routes to acquiring the fuel for a nuclear bomb. One involves separating and concentrating one isotope of uranium, a process called enrichment. If uranium is enriched by a small amount, then it may be used to generate electricity in a nuclear power reactor. If uranium is enriched to high levels, then it may be used in a nuclear bomb.
The other route to acquiring the fuel for a nuclear bomb is called reprocessing. It involves separating plutonium from the byproducts of running a nuclear reactor.
Experts tend to focus on the enrichment route because Iran has built gas centrifuge enrichment facilities at Natanz and Fordow (Qom). In addition, the restrictions on Iran’s nuclear program under the deal virtually eliminate Iran’s capability to use reprocessing as a route to nuclear weapons, according to research by the Belfer Center for Science and International Affairs.
Assuming Iran pursued enrichment, it would have to choose whether to exploit its declared centrifuge facilities or attempt to conduct all operations in clandestine locations.
Under the deal, Iran can keep some centrifuges at Natanz, to make a small amount of fuel for nuclear power reactors, and at Fordow for various medical applications. IAEA safeguards make it almost impossible for Iran to secretly switch these centrifuges from peaceful use to the production of fuel for nuclear weapons. Inspectors have daily access to the facilities, plus equipment continuously monitoring the level of enrichment being achieved by Iran’s centrifuges. That would detect any switch from producing reactor fuel to weapons fuel. The IAEA also uses tamper-indicating seals and surveillance systems to verify that equipment is not being removed or altered when inspectors are away.
For the next 10 years, the deal also strictly limits the numbers and types of centrifuges, which slows down Iran’s ability to enrich uranium. If Iran decided to break the deal and started using all its known centrifuges to produce weapons-usable nuclear fuel, it would take roughly 12 months for the centrifuges to produce enough fuel for one weapon. That would give other countries time to stop Iran, including by threatening to destroy, or actually destroying, the Natanz and Fordow sites.
Building a clandestine facility
Iran could try to build a clandestine enrichment facility. While it would not necessarily stand out in satellite imagery, Iran would, nevertheless, face a series of technical and practical challenges.
A past attempt at a secret enrichment plant was detected by Western intelligence agencies and exposed by the National Council of Resistance of Iran, well before it could become fully operational. There is little reason to think Iran would be more successful in concealing a facility today.
Iran also would have trouble secretly building enough centrifuges to fill a hidden enrichment plant. Some of the basic materials, such as high-strength aluminum and steel, could be diverted from Iran’s existing nonnuclear industrial activities. However, many other essential components, particularly for the centrifuge bearings, vacuum systems and sensitive electronics, could realistically be acquired in sufficient quantities only by importing them.
Under UN Security Council Resolution 2231, which accompanies the deal, all countries must get Security Council approval before transferring any “dual-use” technology to Iran, such as vacuum pumps and precision machining tools. These are items that could be used in nuclear work but also have peaceful applications such as information technology and medicine. As a result of this restriction, Iran would almost certainly need to build a sophisticated smuggling operation.
The United States, its allies, and like-minded countries have been moderately successful in intercepting suspicious transfers of nuclear-related technology, even when suspect countries hide behind front companies. The most famous example is the 2003 interception of centrifuge parts aboard the freighter BBC China, which unraveled Libya’s nuclear weapons program. But with dual-use technology, one of the challenges has been distinguishing suspicious transfers from legitimate ones.
This deal is quite clear: All transfers of dual-use technology from any country to Iran, even for use in nonnuclear industries, are prohibited unless the supplier has received approval from the Security Council. If an intelligence organization detects the transfer of any sensitive piece of technology that has not been preapproved by the Security Council, it will stand out as a clear violation.
Iran would also need to staff its covert operations. It has many scientists and engineers, but diverting enough people from their regular jobs to a covert facility would be difficult to hide, particularly from watchful dissident groups like the National Council of Resistance of Iran.
Keeping the plant operating
Assuming that Iran managed to construct, equip and staff the covert enrichment plant, the next challenge would be to operate the plant for long enough to produce enough enriched uranium for at least one nuclear weapon without being discovered.
The IAEA has the right to request access to suspected covert nuclear sites. Once there, inspectors can test the environment – swabbing building walls or collecting soil samples to test for nuclear material. This has previously detected small covert enrichment operations in Iran.
If Iran refuses access, then it must quickly prove the site is benign. It would not be able to stall for long enough to remove or decontaminate an enrichment plant so completely as to foil expert detection. An outright refusal to allow inspectors access to the site would be open defiance of the deal – allowing other countries to infer that it is in fact a covert nuclear site.
Looking at the deal as a whole, Iran’s best strategy for acquiring nuclear weapons would simply be to wait for restrictions on its declared enrichment program to be lifted.
Assuming that the deal does not fall apart sooner, most of those provisions are scheduled to expire in 2030. In the meantime, the deal helps make a nuclear-armed Iran a less immediate prospect.