Why China changed its mind about nuclear weapons and is bulking up its arsenal at 'accelerated' pace

• China's rapid military expansion in recent years has alarmed other countries.
• China's nuclear arsenal is much smaller than the US's, but US officials are warning about its growth.

The US Department of Defense's annual report on China's military, released in November, again illustrated the breathtaking pace and scale of China's conventional military modernization.

This year's report also highlighted a number of developments that could threaten the US more directly than China's conventional forces — namely China's "large-scale expansion of its nuclear forces."

That expansion is well documented. The Pentagon's 2020 report on China's military noted that Beijing's stockpile of nuclear warheads would at least double by the end of the decade.

But this year's report includes a more urgent message: China "has accelerated its nuclear expansion" and is "exceeding the pace and size the DoD projected in 2020," the Pentagon says.

This month, a Chinese arms-control official denied those assertions, but Beijing's work is still seen as troubling. It's also a reminder of just how small China's nuclear arsenal was and is compared to other major powers, and it shows how dramatically Chinese thinking about nuclear weapons has shifted in recent years.

A smaller arsenal

The Pentagon estimates that China's stockpile of nuclear warheads is in the "low-200s," though others put it as high as 350.

By comparison, the US and Russia are believed to have 5,550 and 6,225 warheads, respectively, though they have agreed to limits on how many can be deployed.

The lower estimate isn't that much larger than other nuclear powers. The UK is believed to have 225 warheads, France 290, India 156, and Pakistan 165. Israel and North Korea are believed to have stockpiles ranging from several dozen to a few hundred warheads.

China's smaller arsenal is in part a legacy of Sino-Soviet dynamics during the Cold War.

China initially received extensive help on its nuclear weapons from the Soviet Union, but the Sino-Soviet split in the late 1950s left China on its own. Beijing detonated its first nuclear weapon in 1964 and its first thermonuclear weapon in 1967.

While other powers developed multiple delivery systems — the air-, ground-, and sea-launched weapons of the nuclear triad — Beijing initially struggled to do so, and the high cost of such weapons further limited how many China, then one of the poorest countries in the world, could make.

Moreover, the need to modernize its military in the face of more immediate conventional threats limited the resources China could spare on nuclear weapons. China also adopted a "no first use" policy, essentially precluding their use as offensive weapons.

"Given limited defense resources, the Chinese mainly focused on conventional forces and the modernization of a small deterrent nuclear force," Timothy Heath, a senior international and defense researcher at the RAND Corporation think tank, told Insider.

Nuclear buildup

As the Cold War ended, China's threat perception changed. The Soviets disappeared, while the US became something of a partner.

Those shifts in the 1990s and early 2000s allowed China to become the world's second largest economy, which in turn enabled its immense military modernization effort. China first focused on conventional capabilities, but that effort has expanded.

"There is plenty of money available to buy fancy platforms like stealth aircraft, aircraft carriers, and a much larger nuclear arsenal," Heath said.

The Pentagon says China hopes to have 700 deliverable nuclear warheads by 2027 and at least 1,000 warheads by 2030. According to the report, China is constructing "fast breeder reactors and reprocessing facilities" that will increase its capacity to produce plutonium to support this expansion.

China's is also expanding and modernizing all legs of its nuclear triad.

It is building more silos on the ground and increasing its ICBM arsenal, currently estimated to number about 100. In 2020, China launched over 250 ballistic missiles, exceeding the total launched in 2018 and 2019.

The Chinese are also implementing a launch-on-warning posture they call "early warning counterstrike," which relies on large ground-based phase-array radars and geostationary early-warning satellites, at least one of which is already in orbit.

China's navy is adding more Type 094 Jin-class nuclear-powered ballistic-missile submarines. Type 094 subs are armed with JL-2 sub-launched ballistic missiles, the range of which requires the subs to operate around Hawaii in order to reach the continental US.

But, according to the Pentagon, China is working on a newer sub, the Type 096, to pair with a new missile, the JL-3, that could reach the US mainland from Chinese waters.

China's air force has adopted the H-6N, the latest variant of its H-6 strategic bomber. The H-6N can conduct aerial refueling, which extends its range, and carry air-launched ballistic missiles. Last year, an H-6N was spotted carrying what was believed to be a hypersonic missile.

Deterrence

The overarching goal of China's military modernization is to reach parity and establish deterrence with the US.

China fears the US — with more nuclear weapons and a mature triad — could launch a preemptive strike against China's nuclear arsenal and launch capabilities, leaving China without adequate defenses. This has led Beijing to pursue more weapons and delivery systems so it has enough to survive an attack and to overcome US missile defenses.

"What they are trying to do is build enough missiles on enough platforms that the Chinese can be absolutely confident that they can get missiles past US defenses and strike US territory in the event of nuclear war," Heath said. "The Chinese hope to make it impossible for the US to be confident it can carry out a preemptive strike that annihilates China's nuclear capabilities."

The US has called on China to join talks on an arms-control agreement similar to those between the US and Russia, but Beijing has shown no interest, pointing to the US's larger stockpile and lack of a "no first use" policy.

While the expansion of its nuclear arsenal may be the clearest example of China's preparation for a potential conflict, it's just one element of a broader buildup that troubles military officials and policymakers.

"It's important to see the modernizing nuclear arsenal as part of the bigger picture, in which the Chinese are building up their military capabilities in space, cyberspace, and in the conventional force," Heath said. "It's all happening at the same time."