Understanding the Challenges of Nuclear Weapon Development

Uranium and enrichment: the quest for U-235

To understand why the manufacture of nuclear armaments is so difficult, it is first necessary to take an interest in basic fissile materials used to create a nuclear explosion: uranium and plutonium.

Uranium is the starting point, but in its natural state, it is not reactive enough to trigger a nuclear chain reaction. Natural uranium is mainly composed of the U-238 isotope, which is fissile, is indeed far too little reactive to be used in a nuclear weapon.

The tip lies in the enrichment of this uranium. The objective is to increase the proportion of the U-235 isotope, which is much more reactive than the U-238. But this task is not as simple as it looks. The enrichment process consists in extracting this rarer isotope from the rest of the natural uranium, which, in its raw form, contains only 0.7 % of U-235. To reach the levels necessary for a nuclear weapon, it is necessary to isolate more than 90 % of U-235, which requires sophisticated installations and advanced technology.

Enrichment, on the other hand, requires centrifuge that separates the isotopes from uranium by the difference in their mass. This process, in addition to requesting colossal resources, requires extremely specific expertise and expensive equipment. And that's not all: you also have to be extremely careful, because the uranium hexafluoride used for this process is highly toxic, and leaks or errors can have dramatic consequences.

Plutonium: another fissile material, but difficult to handle

In addition to uranium, another key element in the manufacture of nuclear weapons is plutonium-239 (PU-239). This plutonium is not present in nature in sufficient quantities and must be manufactured. In nuclear reactors, uranium-238, by capturing neutrons, turns into plutonium-239 after a series of reactions. This plutonium-239 is a fissile isotope capable of releaseing immense energy when it undergoes a fission reaction.

However, making plutonium and extracting it from irradiated nuclear fuel is an extremely complex process. First, plutonium is mixed with other fission products in a reactor. To extract a pure quantity, use fuel reprocessible techniques. These techniques are not only expensive, but they also have considerable risks for workers' safety and the environment, due to the intense radioactivity of plutonium.

Manipulation of plutonium is therefore a risky company. Once extracted, it must be carefully purified before being able to be used in nuclear weapons. This is why only a few countries with advanced industrial and scientific capacities are able to carry out these processes.

Credits: Dragon Claws/Istock

The necessary infrastructure: high technology

It is not enough to control the enrichment of uranium or the extraction of plutonium to make a nuclear weapon. The creation of a bomb requires impressive infrastructure. This includes nuclear reactors, specialized centrifuge, high security laboratories and fuel reprocessing facilities.

Building these infrastructure requires colossal investments. For example, the implementation of a uranium enrichment factory or a plutonium reprocessing installation requires qualified workforce and advanced equipment. These technologies must be protected from any attempt to sabotage or espionage, which adds an additional layer of complexity and cost.

In addition, although technology exists to produce these weapons, the manufacture and tests of nuclear bombs have enormous risks, not only in terms of security but also in terms of geopolitical stability. Outdoor nuclear tests have been largely prohibited by international treaties, and most tests are now carried out via extremely expensive computer simulations.

Geopolitical risks and international pressures

Beyond technical and financial challenges, the manufacture of nuclear armaments is also governed by severe geopolitical constraints. One of the most important instruments to limit nuclear proliferation is the Treaty on Non-Proliferation of Nuclear Weapons (TNP), signed by 190 countries in 1968. This treaty aims to prevent the spread of nuclear weapons, by inciting nations to limit their military nuclear program and work for disarmament.

Nations trying to develop nuclear weapons outside this framework are faced with intense international pressure, both diplomatic and economically. Sanctions can be imposed, and military actions can even be envisaged to prevent these developments. In addition, the International Atomic Energy Agency (AIEA) leads regular inspections to ensure that countries respect the commitments made within the framework of the TNP.

This is why, although some countries like India, Pakistan, Israel and North Korea have succeeded in developing nuclear arsenals, they must constantly face international pressures to prevent the proliferation of these weapons.

Mastering complex know-how

Ultimately, the manufacture of nuclear weapons is an extremely complex and expensive process, which requires advanced technological and industrial capacities, rare expertise, and considerable financial resources. The enrichment of uranium, the manufacture of plutonium, reprocessing and test infrastructure, as well as the handling of highly dangerous radioactive materials, constitute as many major obstacles to the production of these weapons.

Beyond the technical challenges, nuclear proliferation is also a highly political subject, and international treaties like the TNP exert constant pressure on countries which plan to acquire nuclear weapons. This explains why so few nations have nuclear weapons, despite the availability of technology.

Thus, although the manufacture of a nuclear weapon is technically possible, it remains a complex, risky and costly company, reserved for a handful of countries which have both the necessary resources and expertise.

Source: LiveSciencece