How China's Nuclear Arms Buildup Will Make a Tripolar World, and What it Means for Peace

In late June 2021, satellite images revealed that China was building 120 intercontinental ballistic missile (ICBM) silos on the edge of the Gobi Desert. This was followed by the revelation a few weeks later that another 110 missile silos were under construction in Hami, in Xinjiang Province. Together with other planned expansions, these sites amount to a dramatic shift in the country’s approach to nuclear weapons. For decades, China maintained a relatively small nuclear force, but according to current U.S. intelligence estimates, that arsenal is now on track to nearly quadruple, to 1,000 weapons, by 2030, a number that will put China far above any other nuclear power save Russia and the United States. Nor does it seem likely that Beijing will stop there, given President Xi Jinping’s commitment to build a “world class” military by 2049 and his refusal to enter into arms control talks.

It is hard to overstate the significance of this effort. In developing a nuclear arsenal that will soon rival those of Russia and the United States, China is not merely departing from its decades-old status as a minor nuclear state; it is also upending the bipolar nuclear power system. For the 73 years since the Soviet Union’s first nuclear test, that bipolar system, for all its flaws and moments of terror, has averted nuclear war. Now, by closing in on parity with the two existing great nuclear powers, China is heralding a paradigm shift to something much less stable: a tripolar nuclear system. In that world, there will be both a greater risk of a nuclear arms race and heightened incentives for states to resort to nuclear weapons in a crisis. With three competing great nuclear powers, many of the features that enhanced stability in the bipolar system will be rendered either moot or far less reliable.

There is nothing the United States can do to prevent China from joining it and Russia as the world’s top nuclear powers, but there are things that U.S. strategists and defense planners can do to mitigate the consequences. For starters, Washington will need to modernize its nuclear deterrent. But it will also need to engage in new ways of thinking about the nuclear balance of power and how, in a far more complex strategic environment, it can maintain deterrence and keep the nuclear peace.

GUNFIGHTERS ON A DUSTY STREET

During the Cold War, both the Soviet Union and the United States were able to focus their nuclear strategies almost entirely on the other. The two superpowers built nuclear arsenals exceeding 20,000 weapons apiece, allowing them to largely discount the arsenals of the minor nuclear states—China, France, Israel, and the United Kingdom—whose stockpiles did not exceed the low hundreds. After the Cold War, Russia and the United States felt comfortable agreeing to reduce their deployed strategic forces to 1,550 nuclear weapons, as they continued to maintain a large advantage over any other nuclear-armed state.

Although the bipolar system did not eliminate the risk of nuclear war, it worked well enough to avoid Armageddon. Two features of the two-power system are parity and mutually assured destruction, or MAD. Ever since they initiated the Strategic Arms Limitation Talks, in 1969, both Moscow and Washington have emphasized maintaining parity, or similar-sized arsenals, as a way to enhance deterrence and crisis stability—a situation in which there are strong disincentives to resort to nuclear weapons, even under conditions of great stress. For both powers, establishing nuclear forces that were similar in size and far larger than that of any other nuclear state placed them on an equal footing. This was especially important for the United States, which sought to discourage Soviet attacks not only on itself but also against key allies and security partners, whom Washington had offered to shelter under its “nuclear umbrella” through extended deterrence. Consequently, Washington was keen to avoid creating the perception among these states that its nuclear forces were in any way inferior to Moscow’s.