China does not voluntarily disclose information about the size of its nuclear arsenal. But that is no reason to speculate about the magnitude and purpose of recent improvements. Independent analysts of China’s nuclear program have enough reliable information to make a few definitive statements about Chinese nuclear capabilities and intentions.
We know China produced a limited amount of weapons-grade plutonium before joining a voluntary moratorium on production several decades ago. We also know China conducted a limited number of explosive nuclear weapons tests. Those two critical factors constrain the future quantity and quality of China’s nuclear forces.
China has a few hundred nuclear warheads and enough weapons-grade plutonium to make several hundred more. The United States has 3,800 nuclear warheads (active and reserve) and enough weapons-grade plutonium to make approximately 5,000 more.
China could currently deliver 75 to 100 of those nuclear warheads to targets in the United States via ground-based intercontinental ballistic missiles (ICBMs) and a maximum of 60 more on its soon-to-be 60 submarine-launched ballistic missiles (SLBMs). The United States currently deploys 400 nuclear warheads on its 400 ICBMs and about 900 nuclear warheads on its 248 SLBMs, but could deliver as many as 800 ICBM warheads and 1,900 SLBM warheads. The United States also currently deploys 1,010 nuclear gravity bombs and 528 nuclear-armed cruise missiles that are delivered by aircraft. China does not currently deploy any of its nuclear weapons on aircraft.
Given those numbers, the rate of recent increases in the number of Chinese nuclear warheads targeting the United States will not allow China to catch up or even come close to U.S. totals. Even if it does nothing, the United States can maintain this inordinate nuclear superiority over China for many decades to come.
In addition to this huge quantitative advantage, the United States also enjoys an enormous qualitative edge. The United States conducted a total of 1,054 explosive nuclear weapons tests before signing the Comprehensive Nuclear Test Ban Treaty (CTBT) in 1996. Frequent testing helped U.S. designers use plutonium more efficiently and experiment with many different warhead designs. Currently, the United States has seven different types of nuclear warheads, two of which have adjustable yields. It has the capability to strike Chinese targets with nuclear warheads with yields as small 0.3 kilotons and as large as 1.2 megatons with 11 other yield options in between.
China conducted a total of 45 explosive nuclear weapons tests before signing the CTBT. It only has three high-yield options: a several hundred kiloton warhead for its solid-fueled ICBMs and SLBMs, a 2-megaton warhead for its liquid-fueled intermediate range missile and a 5-megaton warhead for its liquid-fueled ICBM. None of those yields is suitable for what Americans call “tactical” or “nonstrategic” nuclear weapons.
Chinese nuclear experts argue that China does not need tactical nuclear weapons since China is not preparing to start or fight a nuclear war with the United States. They also don’t believe the United States is likely to start a nuclear war with China, at least as long as China remains able to retaliate should the United States strike first. That is not a high bar to meet. This is why China’s leaders seem content with a comparatively small and simple nuclear force that, unlike the U.S. force, is kept off alert.
Chinese strategists do worry the United States may mistakenly believe it could avoid Chinese nuclear retaliation by combining a massive first strike with ballistic missile defenses good enough to intercept whatever a first strike might miss. China’s comparatively modest modernization efforts are intended to prevent any U.S. president from taking that risk. Chinese leaders seek to convince their U.S. counterparts that enough Chinese ICBMs can survive a U.S. first strike and that these survivors can penetrate U.S. missile defenses.
The best way for Congress and the American public to address legitimate concerns about China’s nuclear modernization program is to constrain it with two binding international arms control agreements: the CTBT and the Fissile Material Cut-off Treaty (FMCT). Ratification and entry into force of the CTBT would verifiably prevent China from resuming explosive nuclear testing it would need to develop more efficient and varied warhead designs. Successfully negotiating the entry into force of the FMCT would verifiably cap the size of China’s nuclear arsenal at its current level.
China repeatedly has expressed a willingness to participate in international nuclear arms control negotiations in the United Nations. Chinese participants in multilateral nuclear dialogues have said that China will ratify the CTBT when the United States does. China also has stated it is open to beginning negotiations on the FMCT.
China’s willingness to accept these constraints on its nuclear forces is worth remembering when considering questions about the magnitude and purpose of its current modernization programs.
Dr. Gregory Kulacki is the China Program Manager at the Union of Concerned Scientists. Follow him on Twitter @gkucs.