Nuclear Tests: Lessons Learned and Long-Lasting Challenges


By Elisa Morin, Consultant, IB Consultancy

Although nuclear testing might sound like an outdated topic to most of us today, it still plays a significant role in today's world affairs. This was recently proven by the release of a study carried out by French news website Disclose, researchers from Princeton University and British firm Interprt on the true impact of France’s nuclear test in the Pacific from the 1960s to the 1990s. According to the researchers, around 110,000 people in French Polynesia have been affected by the radioactive fallout of these tests. So, after more than 70 years of nuclear tests; what were the lessons learned by the international community, which measures have been implemented, and perhaps most importantly; what remains to be done in order to counter this determining global issue?

Current state of play

When writing about nuclear testing, the first challenge comes from the absence of a universally approved definition of the matter. This issue impacts most legislations’ very essence to restrict the testing of a nuclear weapon by broadening or limiting their scope. As an example, according to the Comprehensive Test Ban Treaty Organization, “a nuclear test is defined as a nuclear explosion detonated for either military or peaceful purposes” whereas, for the Collins Dictionary, it is “the process of carrying out a test on a nuclear weapon to determine effectiveness, etc.”.

Finding figures, for that matter, does not pose such a challenge! 2000 nuclear tests have been conducted between 1945 until 1996 by the nuclear states, namely China, France, India, Russia, the United Kingdom, and the United States. After 1996, only 10 more tests were conducted by the Democratic People’s Republic of Korea, India, and Pakistan.

To give our readers an idea of the severity of these multiple tests: from 1946 to 1958, 67 nuclear bombs were detonated on the Marshall Islands, the equivalent of more than 1.5 Hiroshima-sized explosions every day for 12 years. As you can imagine, the environmental and health impact of such explosions is critical.

What nuclear test - a typology

Commonly, we differentiate five “traditional” types of nuclear tests. During the 1950′s and 60′s, most of the tests were atmospheric nuclear tests, mainly because it was the easiest and cheapest way to conduct and evaluate one’s arsenal. The downside of this type of test is its undeniable environmental and health impact due to the number of radioactive particles that spread around the globe. Some extra-atmospheric tests were also conducted as they proved to be beneficial to determine the feasibility of nuclear weapons as anti-ballistic missile defense or anti-satellite weapons. However, these extra-atmospheric tests were set aside due to difficulties states faced with controlling the tests and the significant damage they caused, sometimes even to their power facilities on the ground. Underwater tests have usually been conducted to evaluate nuclear weapons’ effects against naval vessels or to evaluate potential sea-based nuclear weapons. If conducted too close to the surface, underwater tests can contaminate nearby ships or structures. Underground nuclear testing made up the majority of nuclear tests by the United States and the Soviet Union during the Cold War as it was the only form of nuclear testing that remained authorized after 1963. Although underground nuclear testing emits a negligible amount of fallout when the explosion is fully contained, it largely contaminates the underground and can result in seismic activity. Finally, subcritical nuclear tests simulate aspects of nuclear explosions using chemical explosives. It is called “subcritical” because the amount of special nuclear material used in this test is not enough to initiate a chain reaction.

In addition to these five traditional types, it is worth mentioning computer simulation, which uses sophisticated non-nuclear experiments and computer models to predict the performance of nuclear weapons. The advantage of the computer simulation is obvious: countries can maintain their arsenal and avoid any of the environmental effects of physical tests. Some physicians even argued that they had gained a new understanding beyond what was learned from explosive tests. However, many skeptics still argue that although computers are helpful, they are not a substitute for testing. Furthermore, from the 1,054 US nuclear tests that were conducted between 1945 and 1992, the data of about only 200 are still relevant to today’s arsenal. The question is: how long will it be until the USA needs to physically test its new arsenal to have updated data to use in a computer simulation?

Founding treaties – Limit nuclear tests to limit proliferation

The year 1996 marked the last year of testing for China, France, Russia, the United Kingdom, and the United States. Moreover, after 1963, only underground testing remained legal. All of these dates match, in fact, with the instauration of founding treaties, in an attempt to control nuclear testing.

Limiting nuclear testing has never only been an attempt from a minority to put an end to the environmental damages induced by nuclear testing. It has always been at the core of international non-proliferation policies as it prevents vertical and horizontal nuclear proliferation. Indeed, no country can nowadays realistically claim to possess a functioning nuclear weapon without having had the opportunity to test it, so without testing, horizontal proliferation does not exist either. Moreover, although this might now be disputable with the advancement of computer simulation, it is obviously more difficult for any nuclear state to improve its arsenal without testing it, thus preventing vertical proliferation. The Indian Prime Minister Jawaharlal Nehru was the first to raise awareness on the matter in the UN in 1954 by proposing a worldwide nuclear test ban. Almost ten years later, in 1963, the Partial Test Ban Treaty (PTBT) was signed by the United States, the Soviet Union, and the United Kingdom. Although this treaty is definitely a milestone in terms of the nuclear test ban, as it prohibited all nuclear weapons explosions except for those conducted underground, it was quite limited for several reasons. Among other things, the treaty did not provide international verification and did not ban underground testing, and finally was not signed by France and China. In fact, one year after the PTBT’s entry into force, the non-signatory China conducted its very first nuclear test (Project 596) and became the world’s fifth nuclear power. Even more striking, more US nuclear tests were conducted during the decade following the ratification of the PTBT (1963–1972) than in the prior decade (1953–1962).

More recently, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was negotiated in Geneva between 1994 and 1996, with the objective to ban nuclear explosions everywhere: on the Earth’s surface, in the atmosphere, underwater and underground. 184 countries have signed the Treaty, which will only enter into force after the ratification of forty-four specific nuclear technology holder countries.

(...) the way towards a world without nuclear tests is long and paved with various hindrances.

Focus on the CTBT

The verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) is designed to detect any nuclear explosion conducted on Earth, whether it is underground, underwater, or in the atmosphere. To do so, the treaty relies on the International Monitoring System (IMS), composed of 321 monitoring stations and 16 laboratories around the world. These 337 facilities monitor the planet for any sign of a nuclear explosion through seismic sensors or seismometers, underwater hydrophone sensors, infrasonic sensors, and radionuclide stations.

Although the verification regime is clearly a step forward to prohibit nuclear tests, the CTBT also has its flaws. First of all, it is insufficient from a non-proliferation perspective as it does not prohibit non-nuclear explosions that may be relevant to maintaining nuclear weapons such as hydrodynamic tests, hydro, nuclear experiments, or computer simulations. Furthermore, the implementation of the treaty is facing a lack of political will from major actors of the international community who have nuclear weapons. Of the 44 countries that have to ratify the treaty for its entry into force, only 36 have done so. China, Egypt, Iran, Israel, and the United States have not ratified it, while Pakistan, India, and North Korea have not even signed. Nuclear tests performed by North Korea after 2006 brought attention to this significant breach in the treaty, a breach that would nevertheless become its very strength if these countries ended up ratifying it.

To conclude, the way towards a world without nuclear tests is long and paved with various hindrances. This does not mean that progress has not been made. Indeed, it is essential to emphasize the importance and the wider scope of actions of the CTBT. The data collected by the IMS is crucial to mitigate disaster, as proven in March 2011 in Japan. Seismic and hydroacoustic stations enabled national tsunami warning centers in the region to issue timely warnings, which are key to any efficient emergency response. Furthermore, the CTBT, along with treaties on nuclear non-proliferation, has already changed the international community’s mindset. In fact, the norm of nuclear testing has shifted quite radically. Only six nuclear tests have been detected since 2006, in contrast to over 2000 tests between 1945 and 1996. The countries conducting these tests do not represent the norm anymore in terms of nuclear policy. A good illustration of this general movement is the entry into force of the Treaty on the Prohibition of Nuclear Weapons (TPNW) in January 2021. What better way to move forwards to a nuclear-weapon-free world than a treaty explicitly and unequivocally prohibiting the use, threat of use, development, production, testing, and stockpiling of nuclear weapons?

Elisa graduated from the University of Bordeaux with a “Global Security and Analysis” Political Science master's degree in 2019. After working as a research and analyst trainee for a risk and strategic consulting firm in Paris, she joined the IBC team in November 2019.