Nuclear games at Lop Nur

Last week, reports emerged that China has been conducting sub-critical or zero-yield nuclear tests at its Lop Nur site in Xinjiang. A US State Department report made the claims, raising concerns that Beijing may not be adhering to its promise of complying with the ban on zero-yield nuclear-weapons testing. People’s Republic of China (PRC) leaders have denied the reports, which should hardly come as a surprise. Beyond the distractions resulting from the COVID-19 pandemic that tend to conceal any incidence of testing, the reliability of a state’s nuclear arsenal is the principal reason why a nuclear weapons state might conduct sub-critical testing. The volume of data derived from “hot” tests conducted in the range of 10-200 tonnes is crucial in this regard. In 1995, as the Comprehensive Test Ban Treaty (CTBT) negotiations were underway at the Conference on Disarmament (CD), there was resistance from France and the Russian Federation, along with the PRC who sought to have provisions introduced to pursue testing in the 10-200 tonne range. Preserving the opportunity for further testing within this range has been attractive to any existing or potential nuclear weapons state, and will continue to be so.

Such tests would generate more data, thereby enhancing the possibilities for computer simulation and sub-critical or zero-yield tests. To be sure, no such terms were retained when the CTBT was adopted. However, sub-critical testing is permitted under the provisions of the CTBT, as it is only a conventional explosion and does not require an atomic detonation or the release of fissionable energy. All the designated Nuclear Weapons States (NWS) under the Nuclear Non-Proliferation Treaty (NPT) are signatories to the CTBT, including the PRC. The latter, however, along with the US, have yet to ratify the CTBT; consequently, the CTBT has yet to come in force.

In the mid-1990s, the PRC had good reason to resist the adoption of a treaty that would prohibit “hot” testing. Amongst all the Permanent-5 (P-5) or NPT-designated NWS, China has the lowest number of tests at 45, sharing the spot with the United Kingdom (UK). The British, of course, have a nuclear arsenal that is dependent on American support for servicing and maintenance. The PRC, for its part, requires no such assistance. The insufficient number of “hot” tests undertaken by China — and consequently the low data — coupled with a prolonged moratorium, has taken a toll on the reliability and safety of the Chinese nuclear arsenal. While Beijing agreed to adhere to a moratorium on testing in 1996 when the CTBT was adopted, in the intervening years, the pressure internally to test may have grown.

Nuclear scientists, at least within the American nuclear establishment, hold the view that testing is unnecessary to limit or prevent the degradation of weapons-grade plutonium that would undermine the safety and performance of nuclear warheads. However, the introduction of new warhead designs into the nuclear arsenal may also necessitate actual tests to ensure reliability, safety and performance of warheads. China may have been compelled to test to validate the new designs that it is inducting into its arsenal. China has refused to share data from its International Monitoring Stations (IMS) to the International Data Center (IDC), which falls under the jurisdiction of the Preparatory Commission of the Comprehensive Test Ban Treaty Organisation (CTBTO).

Recent reports on Chinese tests may yet later prove to be merely speculative, given that even clandestine nuclear testing cannot escape detection by the International Monitoring System (IMS), and specifically American surveillance and monitoring. China, however, faced a critical shortfall at the time the CTBT was adopted more than two decades ago — Beijing had little computer modeling capacity to conduct sub-critical or zero-yield nuclear tests. Indeed, this was one of the reasons why Beijing initially demurred on signing the CTBT. If the PRC were to maintain and ensure the reliability, particularly the high-yield segment of its nuclear arsenal without “hot” testing, it had to acquire supercomputing capabilities to offset the loss of actual nuclear tests. Given this context, if the latest reports are true of China conducting sub-critical tests at their Lop Nur nuclear test facility, it is reasonable to conclude that Beijing might have been trying to redress, at the least, the computing simulation deficiency and disadvantage it faced 25 years ago. Consequently, it has good reason to conduct sub-critical tests if only to ensure the reliability of its existing stockpile of warheads, or the integration of new designs into its nuclear arsenal.

From a broader strategic perspective, the Republicans in the US have called on President Donald Trump to lift the moratorium on “hot” testing, which Washington has been observing since 1992. US intelligence has documented how Russia surreptitiously conducted low explosive tests in May 2019. Modernising the American nuclear arsenal has been a priority for Trump, authorising the allocation of US$29 billion in the President’s 2021 budget for nuclear modernisation programmes; that budget is a 16-percent jump from the current year. To be sure, Trump’s predecessor, Barack Obama had started the modernisation of US nuclear weapons to obviate the country’s growing obsolescence and to ensure safety and reliability.

At the same time, Washington’s attempt to broaden the bilateral nuclear arms control agreements and include Beijing — such as the New START Treaty between Washington and Moscow, due to expire in February 2021 — has met with stiff resistance from the latter. The PRC does not believe it has a sufficiently large nuclear arsenal to be a signatory to an agreement that reduces the size of its existing warhead stockpile, which it deems too small relative to the Russian and American arsenals. Yet the PRC sits on large inventories of fissile material, which potentially allows it to have an expansive arsenal. Consequently, if Beijing remains intransigent and refuses any substantive engagement with efforts to regulate and limit the size of its weapons inventory, pressures on the Trump administration to resume testing might intensify. Amidst this growing nuclear tension and competition, India too will be forced to revisit its own moratorium on testing which it has been observing since the May 1998 nuclear detonations.

• Privacy & Data Protection
• China
• Comprehensive Test Ban Treaty
• Comprehensive Test Ban Treaty Organisation
• COVID-19
• Lop Nur
• Nuclear Non-Proliferation Treaty
• Nuclear Weapons States
• START Treaty
• XINJIANG

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