On October 31, 1952, the first hydrogen bomb in the United States exploded at the Enewetak Atoll in the Marshall Islands (Getty Images)
In the fall of 1992, the Nevada Desert witnessed the end of America's long nuclear testing history. On September 23, 1992, under the supervision of Los Alamos National Laboratory, the United States conducted a nuclear test code-named "Divider," which was the last nuclear test of the 20th century and part of the "Operation Jolin" series of nuclear tests.
This explosion had limited power, marking the end of a half-century-long nuclear exploration that began in 1945 with the "Trinity" nuclear test, the first nuclear explosion in human history.
The "Divider" nuclear test occurred at a critical moment. The Cold War was about to end; after five decades of ideological and military confrontation with the West, the Soviet Union was heading towards dissolution, while the United States was trying to redefine its superpower role in a unipolar system. At the same time, growing domestic and international pressure called for an end to the nuclear arms race and a re-evaluation of the effectiveness of field testing.
In 1945, the Trinity nuclear test site in the United States successfully detonated the first usable nuclear bomb in a test environment (Getty Images)
During this transition, the purpose of nuclear testing no longer focused on demonstrating force as it did in the 1950s and 1960s when nuclear tests were used as symbols of military prestige, but rather on testing advanced physical components inside small tactical warheads to ensure the reliability of the U.S. nuclear arsenal.
Less than two weeks after the nuclear test, President George H.W. Bush announced a nine-month moratorium on all nuclear tests following the passage of the "Exxon-Hartfield-Mitchell Act" by Congress. The end of the Cold War, the closure of the nuclear test site in Kazakhstan by the Soviet Union in 1989, and Moscow's unilateral announcement of a moratorium on nuclear tests in October 1991 contributed to this action.
With the Clinton administration, this temporary moratorium quickly turned into a permanent one. The Clinton administration adopted a "no nuclear testing" policy and launched the nuclear arsenal management program in 1995. This program focused on monitoring the safety of nuclear warheads through computer simulations and subcritical tests rather than conducting full-scale nuclear tests.
The motivation behind this decision was not entirely political but also stemmed from a profound shift in the understanding of applied nuclear physics. Since 1945, the United States has conducted over 1,000 nuclear tests, accumulating extensive data on the behavior of nuclear materials during fission and fusion, enabling scientists to develop high-precision computer models that simulate the dynamics of nuclear explosions without actual detonation.
By the early 1990s, this shift became the foundation of the "Arms Preservation Program," which changed the testing method from underground explosions to supercomputer simulations. During this process, physical modeling and subcritical tests were used to ensure the reliability of the nuclear arsenal without any further explosive testing.
Over time, this scientific approach gradually became the established nuclear policy of the United States. For the next six decades, including the first term of Donald Trump, six U.S. administrations have maintained a voluntary moratorium on new nuclear explosions, relying instead on physical simulations and advanced computer models to maintain the nuclear arsenal. This long-term commitment effectively marked the end of the U.S. nuclear testing era.
However, President Donald Trump recently decided to resume nuclear testing, breaking a historical consensus that had lasted more than three decades, rekindling thoughts about nuclear explosions as a political tool and a deterrent. Previously, many believed that the United States had completely ended this historical chapter.
Therefore, the question arises: Is there any technical, economic, or political justification for resuming nuclear testing? Or are the existing simulation and non-explosive testing systems sufficient to assess the reliability and effectiveness of the aging nuclear arsenal?
From the Nevada Nuclear Heatwave to Zero Yield
From the Trinity nuclear test in 1945 to the "Divider" nuclear test in 1992, this period marked the peak of the nuclear arms race between the superpowers. During this time, the United States conducted over 1,054 nuclear tests, with more than 800 underground tests conducted in the Nevada Desert. In these tests, nuclear warheads were placed in wells up to 5,000 feet (about 1,500 meters) deep and then covered with insulating materials such as epoxy to prevent radiation leakage to the surface and the ocean.
From a scientific perspective, these large-scale tests aimed to improve warhead design, measure the yield of explosions, and understand the impact of explosions on military facilities and equipment. However, the cost was extremely heavy. Some test sites, such as the Marshall Islands, are still suffering from the consequences of nuclear tests with yields as high as 108 million tons - equivalent to detonating a Hiroshima bomb every day for several years.
But with the arrival of the new millennium, the methods changed. The United States turned to so-called subcritical experiments, which became a practical and safe alternative for collecting key information about the behavior of fissile materials.
In these experiments, a small piece of plutonium or uranium core is wrapped in chemical explosives, generating extremely high pressure and heat. However, the experimental conditions (including mass, shape, and detonation time) keep the material below the critical state, preventing a sustained chain reaction of fission. In other words, no nuclear explosion occurs. Despite this, the generated pressure and pulse are sufficient to emit transient radiation (X-rays and neutrons) and cause instantaneous changes in density and velocity within the sample.
These signals and measured data are precisely recorded and analyzed, yielding data on the behavior of fissile materials under near-explosion conditions. These experimental results are used to build computer simulation models, which form the core of the "Armored Protection" program, allowing the reconstruction of nuclear explosion dynamics with high precision without conducting new explosive tests and assessing the reliability of existing nuclear warheads or their improved designs.
According to the U.S. Department of Energy, as of 2024, the United States has conducted approximately 33 zero-yield nuclear tests. These tests aim to collect data on the behavior of fissile materials (such as plutonium and uranium) under extreme pressure and temperature conditions close to those of an explosion, without triggering a full fission reaction or producing nuclear energy.
The United States is heavily investing in building a new generation of laboratories and research facilities to study nuclear weapon components in real environments without actual explosions (Shutterstock)
Monitoring Plutonium Aging
A report from the U.S. Department of Energy on the 2025 "Nuclear Arsenal Maintenance" plan states that the United States is heavily investing in building a new generation of laboratories and research facilities to study nuclear weapon components in conditions close to real environments, without actual explosions.
The High Explosives Science and Engineering Center in Pecos, Texas, is under construction. It is an advanced integrated facility designed to test conventional explosives used in nuclear warheads and develop safer and more stable materials.
In the Nevada National Security Site, some more ambitious projects are underway, most notably the "Zeus" system. This system is an underground experimental platform used to study the response of plutonium exposed to intense neutron flows. The goal of these experiments is not to produce nuclear energy, but to understand how fissile materials change under radioactive conditions simulating the internal environment of a nuclear explosion.
At the same location, the U-1A Complex (now known as the Key Underground Pulse Test Laboratory) is undergoing upgrades. This laboratory is the core of the U.S. non-explosive nuclear warhead testing program. Within the laboratory, small chemical charges and multi-pulse X-ray imaging equipment are used to record reactions occurring within fissile samples in a billionth of a second.
This location is also developing "Project Scorpius," one of the most advanced X-ray systems in the world. This system allows scientists to observe the response of minute amounts of plutonium to shock waves from conventional explosives. A series of X-ray images are captured at intervals of a billionth of a second, enabling scientists to observe the "micro-explosion" inside the sample as if watching a slow-motion movie.
These experiments aim to achieve two goals: understanding the effects of nuclear aging on plutonium and providing precise data that can be used for future nuclear warhead modernization and maintenance.
Ivan Otero from Lawrence Livermore National Laboratory explained how these facilities are used to monitor plutonium samples that are 80 years old. He explained that over time, this material undergoes radioactive decay, producing tiny helium atoms that become trapped in the metal structure of the plutonium. As these atoms accumulate, they form tiny bubbles that weaken the metal lattice structure, affecting its performance under pressure and consequently the overall performance of the weapon.
The First Nuclear Warhead Developed Under the "Arms Preservation Program"
Through this fundamental shift in testing methods, the United States has been able to develop and upgrade its nuclear warheads without conducting explosive tests.
One of the most notable upgrades is the B61-12 nuclear warhead, an improved version of a conventional gravity bomb. This bomb has completed production and was put into service at the end of 2024. It is equipped with a guidance tail fin system and an internal navigation system, improving accuracy and allowing for yields ranging from tens to hundreds of kilotons. Additionally, its lifespan has been extended by twenty years, meaning higher accuracy and less collateral damage without changing the overall military characteristics of the nuclear arsenal.
As a supplement, the B61-13 nuclear warhead was released in the fall of 2023. This model combines the guidance and safety technology of the B61-12 and has a higher yield, similar to some Cold War-era models, intended for destroying bunkers or hardened targets. This version aims to replace older models like the B61-7, offering more options and operational flexibility in the nuclear arsenal while maintaining modern safety and accuracy. These improvements do not increase the total number of weapons but rebalance the types of weapons in the nuclear arsenal according to the required missions.
In the strategic weapons domain, the W-93 project introduced a new type of nuclear warhead, the first of its kind since the Cold War. It is the first warhead completely designed using the tools of the Arms Preservation Program. This warhead is intended for the Columbia-class submarine-launched ballistic missiles and the Trident missiles.
This project was developed jointly by Los Alamos National Laboratory and Sandia National Laboratories. Its design is based on tested or currently used components, incorporating modern technologies aimed at enhancing safety and reliability standards, simplifying manufacturing and maintenance. The goal of this project is to replace the W-76 and W-88 warheads with safer and more stable ones, thereby improving the safety of storage and transport. Officials claim that the W-93 can be certified without conducting new nuclear explosion tests.
Notably, the letters in the names of U.S. nuclear weapons have actual significance. The letter "W" indicates a missile-launched warhead, while "B" indicates an air-dropped nuclear bomb. The numbers following are not the yield of the weapon but its design sequence. Historically, since the United States developed its first nuclear weapon in 1945, approximately 63 different designs have been put into use, with 46 designed by Los Alamos Laboratory.
Robert Oppenheimer, an American nuclear scientist, in 1954 (French media)
Variable Yield Engineering
This overall trend reflects a practical shift in weapon design. Through what is called "variable yield engineering," U.S. nuclear warheads have become smaller, more precise, and easier to adjust, allowing for the selection of explosion yields based on the target.
In this context, a new low-yield weapon also emerged, such as the W76-2 nuclear warhead, which provides decision-makers with a tactical option to deter opponents without resorting to massive destructive weapons. Analysts believe that these developments indicate increasing confidence in the ability of digital simulations and analyses to determine the required yield scientifically, without relying on live explosive tests.
However, the scientific community is not entirely convinced. Rare technical scenarios, especially when introducing new designs or materials whose behavior has never been observed before, may lead to unforeseen physical phenomena that could exceed the predictive range of simulations.
Therefore, the need for live explosive tests is extremely rare and unconventional, although not entirely impossible in extreme cases. This confirms the stance of the National Nuclear Security Administration's technical officials, who assert that the nuclear arsenal can be maintained without conducting live explosive tests, while some military and strategic experts believe that tests can be resumed in special circumstances.
On the other hand, analysis by the Center for Strategic and International Studies (CSIS) shows that immediately resuming nuclear tests is no longer practically feasible. The test sites, diagnostic equipment, and supply chains have been inactive since the 1990s, and restoring these facilities requires significant investment and a long time to rebuild the infrastructure.
Therefore, whether to resume nuclear testing depends not only on political will but also on technical capability, the readiness of the infrastructure, and whether there is confidence that the nuclear arsenal can be protected and upgraded without actual explosive tests.
In this context, discussions about resuming nuclear testing are sometimes used as a domestic means to demonstrate determination and reshape the image of a "strong America," rather than as a necessary scientific procedure. Trump's decision highlights so-called "nuclear Trumpism" – using deterrence and threats to appease supporters and conservative institutions, who view nuclear testing as a symbol of national prestige.
Revisiting nuclear explosions more caters to nationalist sentiments than strategic logic and revives Cold War thinking in public consciousness, portraying nuclear superiority as a manifestation of America's superpower status.
Remo Reginold, a researcher at the Swiss Institute for International Studies specializing in nuclear security and transatlantic relations, noted that by the time such tests could be conducted, Trump would likely have already left office. Reginold believes that the president is trying to divert attention from more pressing foreign policy issues, such as the decline in his negotiating leverage in the China-U.S. trade conflict, reduced influence in Asian summits and forums, and lack of substantive achievements in Ukraine or real solutions in the Middle East.
Reginold added that raising the issue of resuming nuclear tests is akin to the hype surrounding the possibility of a third term. When such discussions arise, it is essential to carefully examine their true intentions, which are often to divert attention from real issues.
However, the diplomatic costs of such decisions far outweigh their symbolic significance. Washington's willingness to resume nuclear tests would undermine its leadership in disarmament and non-proliferation. It would also provide its rivals, mainly Russia and China, with justifications to expand their own nuclear tests, potentially bringing the arms race back to a state before the 1990s.
Furthermore, the decision to resume nuclear tests reflects a clear disconnect between political rhetoric and scientific reality. Over the past three decades, it has been shown that simulations and subcritical tests are sufficient to maintain a reliable nuclear arsenal, but some politicians prefer to revive old symbols of power to stir up public sentiment.
However, using this topic not only undermines the credibility of U.S. nuclear policy but also weakens public trust in science itself. It replaces accurate scientific knowledge with fear-based and nostalgic rhetoric about former powerful forces. In a world where technology is advancing rapidly and public trust in scientific institutions is declining, the most dangerous experiment may not be taking place in tunnels in Nevada, but rather in the public consciousness.
Sources: Al Jazeera + Electronic Website
Original: https://www.toutiao.com/article/7571984679046365739/
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