Wednesday morning, new evidence emerged that China is expanding its nuclear arsenal. Specifically, researchers at the Center for Nonproliferation Studies have identified the construction of about 119 new silos, most likely for China’s latest intercontinental ballistic missile, known as the DF-41. Previously, only 16 silos at a different site had been identified.
The news is likely to fuel the narrative that China is expanding its nuclear capabilities dramatically. But worst-case assumptions have usually been wrong when it comes to China’s nuclear weapons program. There are good reasons to suppose that they’ll also be off-the-mark in this case.
Here’s why you shouldn’t panic — especially since the U.S. government probably isn’t either.
Yes, China is expanding its nuclear arsenal … but beware worst-case math.
It’s easy to see why this news might result in a furor.
Consider the possible math. China has a relatively small nuclear arsenal, with a warhead stockpile that currently numbers in the “low-200s” according to the Pentagon. For comparison, the United States possesses around 3,800 nuclear warheads, of which around 1,750 are deployed.
There are reports that the DF-41 can carry “up to 10” warheads. So, if China is building more than 100 new missile silos, each armed with a 10-warhead DF-41, worst-case thinking will lead to claims that China’s stockpile is set to increase by more than 1,000 warheads.
China’s missiles will probably carry less than 10 warheads each.
The Pentagon’s arithmetic appears to be different. In a September 2020 assessment, it states that “over the next decade, China’s nuclear warhead stockpile … is projected to at least double in size.” While this choice of words doesn’t totally preclude a quintupling, it gives the strong impression that the U.S. government expects slower and more modest growth.
How can this be?
To start with, the evidence that the DF-41 can carry 10 warheads is flimsy. According to the 2016 news story that appears to be basis for this claim, U.S. intelligence agencies assess that the missile can deliver “between six and 10 warheads.” Moreover, the story reports on two tests of the DF-41, in which the missile carried only two warheads.
Of course, it’s possible that the DF-41 has been tested with more warheads since 2016. However, the Pentagon’s most recent public assessment of China’s military capabilities, published in September 2020, declines to say how many warheads the DF-41 can carry — as does a public intelligence report of global missile threats from January of this year. So, be cautious about any confident predictions of the DF-41 capabilities.
Moreover, it’s entirely possible that China will follow Russia’s lead and deploy at least some of these missiles with just one large gliding reentry vehicle apiece.
Some new silos may be decoys with no missiles — as the U.S. planned during the Cold War.
There are even reasons to wonder whether every silo will be loaded with a missile.
China wants its nuclear forces to be survivable. It worries that the United States, in a conflict, might attack China’s nuclear forces preemptively (with conventional or nuclear weapons).
China has built a vast network of tunnels to help hide, and therefore protect, its relatively small force of mobile ICBMs. In a similar vein, some of the new silos may be dummies, intended to complicate U.S. targeting plans.
In fact, China may even plan to shuttle a small number of ICBMs among a much larger number of silos in a kind of “shell game.”
The United States almost adopted this approach during the Cold War. The Carter administration planned to build a staggering 4,600 silos to protect just 200 MX/Peacekeeper ICBMs, though the Reagan administration ultimately changed the plans. The layout and spacing of China’s new silos are strikingly similar to the Carter administration’s concept.
China’s new missile is probably a response to U.S. defenses.
China also worries that U.S. missile defenses could mop up any of its missiles that survived a U.S. attack and were launched in retaliation. A recent public U.S. intelligence assessment acknowledges that “nearly all of our adversaries are concerned with U.S. missile defenses and have devised various methods to complicate missile defense operations.”
The DF-41 is likely one such countermeasure. It could be used to deliver a glider that can fly underneath U.S. radars and thus evade U.S. defenses. Alternatively, if loaded with multiple warheads, it could help China to overwhelm those defenses by sheer force of numbers.
Understanding China’s motivations is important in developing an effective response.
Follow the fissile material, not the weapons.
So what does this mean for U.S. nuclear policy?
The United States is likely to retain a much larger nuclear arsenal than China. But Washington would like to head off a potential arms race. How can it gain confidence that, despite Beijing’s modernization efforts, the growth in China’s arsenal will remain moderate and slow-paced?
The trick is to follow the fissile material: the plutonium and highly enriched uranium needed to produce nuclear weapons. The Pentagon assesses that “China probably has enough nuclear materials to at least double its warhead stockpile without new fissile material production.” China does not currently appear to be producing more fissile material, though there are concerns that it may restart. (For its part, the United States ceased all production of fissile material for any purpose decades ago.)
One route to avoiding an arms race might be a credible Chinese commitment to use any newly produced fissile material exclusively for civilian purposes or, better still, not to produce any more at all.
Of course, China would be unlikely to make such a commitment until it’s confident in the survivability of its nuclear arsenal. To build such confidence, the United States could commit, in return, to limit its missile defenses — by, for example, not developing or deploying space-based defenses. In fact, it’s actually in the U.S. interest for China to be confident in the survivability of its nuclear deterrent to reduce any pressures on China to use nuclear weapons first in a conflict.
Negotiating the details of such a quid pro quo, including verification, would certainly be challenging. But, then again, the prospect of unrestrained nuclear competition can focus minds in a way that few other security concerns can.
James M. Acton holds the Jessica T. Mathews Chair and is co-director of the Nuclear Policy Program at the Carnegie Endowment for International Peace.
Editor’s note: Since this piece was originally published July 1, additional silos have been discovered at a second new nuclear missile base in China.