China’s nuclear expansion and the increasing risk of an arms race

Why is China expanding its nuclear arsenal? In his new article, Henrik Stålhane Hiim argues that concerns about the vulnerability of its nuclear forces is the main driver – and that there is little evidence of a change in China’s nuclear strategy.

In the summer and autumn of 2021, researchers revealed that China had started building more than 300 silos for intercontinental ballistic missiles in three different fields. The silo exposure made international headlines, and demonstrated that China had started a significant nuclear expansion. The US Department of Defense now assesses that China will possess over 1000 warheads by 2030, a fourfold increase in a decade. Even though the United States and Russia will continue to possess significantly larger arsenals, there is no doubt that China’s buildup represents a turn away from its traditional approach of maintaining a small nuclear force.

There is less agreement about why China is expanding its arsenal. In my article, I argue that there is still little evidence to suggest to that the expansion represents a change in China’s nuclear strategy. Chinese leaders have traditionally thought of nuclear weapons as having two functions: Deterring nuclear attacks from others, and countering nuclear blackmail or coercion. The buildup could enable later shifts in strategy, but there are still few signs of Chinese leaders fundamentally rethinking the purposes nuclear weapons serve in their defense policy.

I further find that the main driver of China’s expansion is concerns about US capabilities such as missile defense and highly precise nuclear and conventional weapons. Chinese sources indicate that worries about US nuclear policy have increased in recent years. Many in China fear the combination of weapons that can target its nuclear forces, and defenses that can intercept any surviving Chinese missiles. In tandem, they argue, such capabilities pose a major threat to China’s nuclear deterrent.

To be clear, other factors may also have influenced China’s buildup. Some analysts point to prestige and status concerns as a possible explanation. Others have indicated that the purpose of the expansion is to create a stronger “shield” to enable conventional aggression against Taiwan, which is possible, but not directly discussed in Chinese sources. Nevertheless, my findings indicate that concern about the vulnerability of its arsenal is likely to be the main driver. In particular, the Donald Trump administration’s Nuclear Posture Review was seen as alarming in China and contributed to increasing worries about the future strategic stability.

Towards an arms race?

My findings have implications for the debates about US nuclear policy. There is increasing discussion in the United States about whether to respond to China’s buildup through a similar expansion and by deploying new weapons systems. In October, the bipartisan Congressional Commission on the Strategic Posture of the United States published its final report. The commission recommended to prepare to upload some or all of the warheads currently held in reserve. It further stated that the United States should deploy additional theater nuclear weapons with variable yield (or so-called tactical nuclear weapons) to the Indo-Pacific region. Similarly, a study group convened by Lawrence Livermore National Laboratory (LLNL) recently argued that “The United States should plan and prepare to deploy additional warheads and bombs from the reserve.”

Unfortunately, my article indicates that such responses are very likely to lead to major arms race pressures. For example, influential US experts have argued that the United States should attempt to maintain a so-called damage limitation capability – that is, the ability to destroy or intercept as many Chinese nuclear weapons as possible in the event of an all-out war. The problem of this approach, however, is that Chinese leaders are no longer willing to live with a vulnerable arsenal. China is very likely to respond if its leaders and experts believe the United States is attempting to maintain a damage limitation capability.

Similarly, if the United States deploys new tactical nuclear weapons in Asia, the likelihood of China developing such weapons may increase. As experts from the Federation of American Scientists highlight, there is still no evidence that China plans to field a new low-yield warhead. However, my article highlights that Chinese experts are debating whether there is a need for such weapons as a response option vis-à-vis the United States.

Different nuclear schools of thought

As other scholars have also highlighted, the competing readings of China’s nuclear intentions, and of how the United States should respond, is in no small part informed by different assumptions and theories about nuclear strategy. Scholars who believe the balance of terror is delicate – and that states have incentives to pursue superiority – are likely to see China’s expansion as alarming. These scholars, whose views also appears to be at least partly shared by U.S. officials, fear China might be opting for a first-strike capability. Moreover, they argue that the United States should attempt to maintain its superior position.

My research demonstrates, however, that fears of China opting for nuclear superiority and a first-strike capability are overblown. Instead, China’s expansion aligns with the so-called nuclear revolution theory. A key tenet of this school of thought it that states should strive for a secure second-strike capability, but that pursuit of superiority is meaningless. So far, China appears to be acting like a good nuclear revolutionary. If it continues to do so, an arms race may still be at hand, albeit one less intense than the Cold War race.

Read the article “The last atomic Waltz: China’s nuclear expansion and the persisting relevance of the theory of the nuclear revolution” here