Nuclear weapons, the US accuses China of the tests: what’s behind it?

The Chinese embassy in Washington DC did not respond to Adnkronos’ request for comment, but in a statement given to the AFP agency, the Chinese Foreign Ministry called the claims “absolutely false”. “China firmly opposes the United States’ attempt to make excuses for resuming nuclear testing,” the statement read.

The opinion of analysts

Second Lucrezia Goldin, sinologist and journalist at Sky Tg24these accusations are a way for Washington to put pressure on China “to sign a nuclear control agreement, after the one with Russia expired and was not renewed in Donald Trump’s silence”. “Once again Washington’s approach with Beijing is one of negotiation. Trump teases the Chinese with accusations of tests. But the real objective is to bring China to the negotiating table and find a compromise. Bargaining: we shoot high, we arrive at a meeting point.”

Relations between China and the United States in the Trump administrationexplains Goldin, they have so far been characterized by a transactional nature, both on a commercial and diplomatic level. The sinologist also points out that the American strategy is a strategy that did not begin with Trump. Already in the tail end of the Biden administration the choice was to shift the policy towards nuclear deterrence towards China.

“No more Russia, no more North Korea. Something that had surprised many analysts, especially because Pyongyang ‘let itself go’, so to speak”, explains Goldin. According to the most recent estimates, as of 2019, China’s weapons arsenal was around 200 units. Now, US intelligence believes China is on track to reach 1,000 warheads by 2030.

Although the major nuclear powers have not detonated a nuclear bomb for decades, this does not mean that work on nuclear weapons has not continued. For example, in the United Statesscientists have begun a program to maintain weapons without testing them, including computer simulations, scientific experiments, and underground explosive tests of nuclear weapons components. These explosions do not trigger a nuclear chain reaction – they are called “subcritical” tests – and therefore do not violate the international moratorium on testing. China and Russia are believed to have similar programs: Russia has been seen modernizing its nuclear facilities, and in recent years, China has expanded its main test site by digging new tunnels.

The United States has long suspected that China and Russia are conducting experiments that actually trigger a small nuclear chain reaction, but part of the problem is that “the Comprehensive Nuclear-Test-Ban Treaty does not define what an explosion is,” it tells Adnkronos Jeffrey Lewis, arms control expert at Middlebury College. According to Lewis, China and Russia could interpret this to mean that small nuclear chain reactions are allowed, as long as the explosion does not become too large. Goldin, for her part, specifies that it is true that China has accelerated the production of nuclear warheads: “But it is also true that compared to Russia and the United States it has many, many fewer. And above all, the modern military capabilities of the People’s Republic of China are for the moment only theoretical and untested”, states the sinologist.

Regardless of what happened in 2020, the US also claims that China is planning tests with “estimated yields in the hundreds of tons.” Such tests, if they were to occur, would fall into a gray area between a small nuclear chain reaction and a large-scale detonation. Ankit Panda, nuclear weapons expert at the Carnegie Endowment for International Peacebelieves that the most plausible hypothesis is that China is carrying out small-scale tests to ensure that its weapons do not accidentally explode.

Panda said that if a weapon failed such a safety test, it could “exceed” its intended output, resulting in an explosion on the order of a few hundred tons. Such a failure would presumably lead to safer weapons designs. The least plausible hypothesis is that China is attempting to test new nuclear weapons designs. According to experts, the tests could be used for the development of devices such as hypersonic missiles or for “small” weapons with nuclear power in the order of tens of kilotons.

The Pentagonaccording to an official consulted by Adnkronos, fears that an expanding Chinese arsenal could be a prelude to an invasion of Taiwan or an attempt to overcome American missile defenses. “China hasn’t explained to us why these changes are occurring. And so in the United States, imaginations have run wild,” the official said.

The analysts examined publicly available seismic data from June 22, 2020 – the presumed date to which the Americans refer – and they found no traces of an explosive test near the Chinese site. The Comprehensive Nuclear-Test-Ban Treaty Organization also said it had seen no seismic evidence of a test. When asked by reporters for more information on the alleged Chinese test, the State Department said it would be released soon, but did not say when. According to analyst Jeffrey Lewis, one reason for the lack of seismic evidence could be that China hid the test through “decoupling”. This technique was also mentioned by the Under Secretary of State for Arms Control and International Security, Thomas DiNanno.

“Decoupling” is another way of saying that the explosion was conducted in a large empty cavity: when the shock wave of the deflagration reaches the walls of the cavity, much of the energy is not transferred to the rock and the explosion seems much smaller than it actually is. However, global monitoring systems are extremely effective, so even with decoupling, it is extremely unlikely that there was a large-scale nuclear test in 2020.

L’China’s nuclear expansion is a major reason the US allowed its latest arms control treaty with Russia to expirein 2026, and are reconsidering nuclear tests. President Trump has said he wants to test “on an equal footing” with other countries, including China. According to Lucrezia Goldin, the Chinese government media speak of an American pretext to justify their nuclear rearmament with related tests. “On Chinese social media – which even though they are a controlled space, they are still an excellent window on Chinese society – several comments remind us that between Beijing and Washington, the one who used nuclear weapons in the past was not China,” says the sinologist.

Jeffrey Lewis, for his part, says he is very worried that all these discussions about testing could start to escalate, without any real stopping point, sending the world back to the days of the Cold War. However, Goldin clarifies how Beijing and its way of doing things has always been very different from that of all the other superpowers and will continue to be so: “In this chess game, China plays black and will take all the time to observe before making a possible move.” (Of Iacopo Luzi)