As the United States and Russia navigate uncharted waters without a nuclear weapons treaty, China’s nuclear buildup is like a storm brewing on the horizon.
Beijing has dramatically multiplied its force since Chinese leader Xi Jinping came to power in 2012. China had kept its stockpile stable at around 200 since the 1970s. It now contains more than 600 nuclear warheads and is projected to exceed 1,000 by 2030, according to a 2025 Pentagon report.
China is moving from a land force to a land-air-sea nuclear triad. It now has six nuclear weapons-capable submarines, and one of them is at sea at all times, experts say. Breaking from its traditional second-strike nuclear posture – a modest force designed to survive a first strike and inflict unacceptable damage on an easy target like a city – it is developing an advanced force capable of destroying enemy nuclear missiles and waging nuclear war.
Why do we write this?
China is engaged in a massive nuclear weapons expansion, increasing the size and capabilities of its arsenal. At a time when the will to curb nuclear proliferation is waning, this could trigger a new wave of competition for nuclear weapons.
“China is on a path to a massive nuclear buildup with very little transparency about the end goal,” says Tong Zhao, senior fellow at the Nuclear Policy Program and Carnegie China. This, he claims, is “driving renewed nuclear competition.”
One of the reasons the Trump administration refused to extend the New Strategic Arms Reduction Treaty (New START) was to gain leeway to respond to China’s rapid expansion, says Dr. Zhao: “(Washington) feels the need to react.”
China’s buildup
China’s leaders remain tight-lipped about their intentions for expanding nuclear weapons, but experts say one overarching goal is clear: a more powerful China.
“Xi Jinping wants China to be strong,” says Jeffrey Lewis, a distinguished scholar of global security at Middlebury College. “Xi Jinping’s vision is to have a nuclear force that is more like Russia and the United States,” which currently control about 86% of the world’s nuclear warheads.
China traditionally maintained a comparatively modest force, and achieving broad parity with the United States and Russia would take time. But Beijing worries that if China appears weak, that could embolden American aggression, experts say.
“President Xi wants a larger nuclear arsenal to counter American perceptions of China’s strategic inferiority,” says Dr. Zhao.
In a public show of force, Xi presided over a large military parade in Beijing in September that unveiled the People’s Liberation Army (PLA)’s newest intercontinental ballistic missile (ICBM), the DF-61. “The goal is to show the rapid advancement of China’s strategic capability,” says Dr. Zhao.
Mark Schiefelbein/AP/File
To be sure, China’s nuclear weapons development has not been without flaws, including, most recently, widespread corruption. In recent years, Xi has overseen a major military purge that has brought in several top commanders of the PLA Rocket Force, which controls the country’s nuclear and conventional missiles. Quality problems discovered in the lids of new silos China has been building may have contributed to the layoffs, experts say.
But it is moving fast enough to unsettle Washington, which had initially called for China to join the nuclear arms control process in 2020, a proposal Beijing rejected. Now, China’s expansion threatens to fuel a new arms race.
“We are likely to see the United States start loading more warheads on missiles,” says Dr. Zhao. “This action-reaction dynamic… will have broader global implications.”
Collaboration with Russia
From the American perspective, China’s nuclear development carries several risks, both geopolitical and technical. A major concern in Washington is that China and Russia could join forces against their common adversary, the United States.
China could then attack Taiwan and Russia could advance toward Europe, “challenging the United States to respond,” says Rose Gottemoeller, a former U.S. diplomat who served as undersecretary for Arms Control in the U.S. State Department and was the chief U.S. New START negotiator. “That is absolutely the worst-case scenario that the United States is contemplating, given what we call the ‘two nuclear pairs’ problem,” he says.
China and Russia almost certainly remain too wary of each other to carry out joint nuclear planning, integrate their forces or threaten a joint nuclear attack on the United States, experts say. But they are increasingly collaborating on nuclear weapons technology and signaling exercises. For example, Chinese and Russian nuclear-capable bombers have conducted joint patrols over the Sea of Japan and the South China Sea to show resolve to Tokyo and Washington.
Moving forward without guardrails
China’s nuclear program is advancing in several key areas that the Pentagon and US analysts consider risky and destabilizing.
These include China’s development of an early warning system, which would use infrared satellites and ground-based radars to allow China to launch a counterattack before the enemy’s first attack can even detonate. Both the United States and Russia have this capability, known as “launch after warning,” as a legacy of the Cold War. It is widely considered the most dangerous nuclear posture because it requires quick life-or-death decisions, and false alarms are common, experts say. In 2019, Russia confirmed that it was working with China to develop an advanced missile attack early warning system. “Such systems mean that political leaders have just minutes to make the most consequential decision in human history,” says Dr. Lewis. “I’m definitely worried about China joining that club.”
Another concern is the orbital bombardment system that China tested in 2021, which would allow it to launch a nuclear warhead and strike with very little warning. “China could use this weapon to carry out surprise attacks against the American leadership or (its) nuclear command and control system,” says Dr. Zhao.
China is also focused on developing forces with dual capabilities: missiles that can carry nuclear or conventional warheads. In times of war, ambiguity about whether an attack is nuclear or conventional “raises all kinds of problems for keeping the nuclear genie in the bottle,” Dr. Lewis says.
This month, the Trump administration accused China of conducting explosive nuclear tests, an accusation that Beijing denied as “baseless.”
As China moves forward with expanding its nuclear arsenal, it has little interest in engaging in talks on arms control or nuclear risk reduction. And the recent expiration of New START, which Beijing called “regrettable,” frees the United States and Russia to modernize and expand their own arsenals, further reducing international political pressure to rein in China.
However, on a positive note, Gottemoeller says, Trump has supported American nuclear experts in continuing to engage with their Russian counterparts. Igor Korotchenko, editor of the Moscow-based National Defense Review and a leading Russian military expert, says Russia is willing to resume talks in the old format or find some formula to expand the limits of New START. Russia’s main concern is Trump’s desire to build an anti-Golden Dome.
anti-missile shield, which would undermine Russian deterrence capabilities and make any form of arms control obsolete, he says.
Additionally, President Trump will have four opportunities to meet with Xi this year. “There are many opportunities in 2026 for the United States and Russia, and separately the United States and China, to meet and talk about reducing nuclear risks and improving nuclear controls,” says Ms. Gottemoeller.
■ Fred Weir contributed to this story from Moscow.
