China's nuclear stockpile has become formidable since 1964. Image: Pacific Forum / iStock

In recent months, China has been building its nuclear arsenal at an unexpected pace, likely with the aim of deterring a US intervention in the event of an invasion of Taiwan and to maintain strategic deterrence through mutually assured destruction (MAD).

According to a fact sheet released by the US-based, non-partisan Arms Control Association, China currently has a mere 350 nuclear warheads while the US has 5,500. However, the US believes that China plans to double its arsenal to 700 deliverable nuclear warheads by 2027 and 1,000 by 2030, exceeding the size and pace that the US Department of Defense (DoD) initially projected in 2020.

“The breath-taking expansion of land, sea, and air-based nuclear delivery platforms, command and control survivability, novel, and asymmetric weapons, and supporting infrastructure is inconsistent with a minimum deterrent posture,” said Admiral Charles Richard of the US Strategic Command this month.

Admiral Richard added that China has already achieved a “strategic breakout” in terms of its nuclear capabilities, including rapid quantitative and qualitative shifts that require the US to make immediate and significant planning and capability changes. He also mentioned that this “strategic breakout points out towards an emboldened China that possesses the capability to employ any coercive nuclear strategy today.”

China’s hypersonic technology adds a particular qualitative edge to its nuclear arsenal. In July 2021, China tested its hypersonic glide vehicle – a fractional bombardment system (HGV-FOB) that flew for 40,000 kilometers with 100 minutes of flight time, the greatest distance and time a land-attack weapon any nation has ever achieved. This technology gives China global strike capabilities, and the ability to defeat any current and likely future missile defense system.

In June 2021, satellite imagery revealed that China may be constructing 250 long-range missile silos in at least three locations, fueling concerns that it is substantially increasing its land-based nuclear arsenal. These silos are believed to be capable of housing the DF-41 missile, which has a range of 12,000 to 15,000 kilometers and can carry up to 10 multiple independently targetable re-entry vehicles (MIRVs).

However, the actual number of nuclear missiles that could be stored in these silos could be much smaller, as China is known to have used decoy silos in the past.

Apart from building more silos, China is also exploring anew the idea of railway-delivered nukes for its land-based arsenal. These mobile launchers could exploit China’s 37,000 kilometers of high-speed track to maximize mobility, survivability and concealment of the land-based element of its nuclear deterrent.

In terms of its sea-based nuclear arsenal, China operates four nuclear-powered Type 94 ballistic missile submarines. Each of these submarines can carry 12 JL-2 submarine-launched ballistic missiles (SLBMs), each of which is believed to carry a single nuclear warhead and possess a range of between 7,200 and 9,000 kilometers.

A Chinese Yuan class submarine surfaces in the Indian Ocean. Photo: Facebook

While these missiles can strike other nuclear states such as Russia and India when launched from waters near China, they do not have the range to threaten the US mainland. However, they can hit US territories such as Alaska, Guam and Hawaii.

However, the Type 94 submarines are believed to be magnitudes noisier than their US and Russian counterparts, which makes them easily detectable. As such, China is working on the Type 96 successor design, which would be armed with the planned MIRV-armed JL-3 SLBM with a range of 9,000 kilometers. By 2030, the US DoD estimates that China could have a fleet of eight Type 94 and Type 96 submarines operating concurrently.

Historically, China has not emphasized the air-based leg of its nuclear arsenal. However, China has developed its own air-launched ballistic missile, which was last tested in 2018. It has also upgraded its long-serving Xian H-6 strategic bomber as a standoff missile launch platform, which itself is based on the Soviet Tupolev-16 bomber.

Moreover, last year China revealed concept art for its H-20 bomber, a stealthy flying wing design reminiscent of the US B-2 Spirit bomber. The H-20 will be armed with nuclear and conventional missiles, have a maximum take-off weight of 200 tons, can carry 45 tons, fly at high subsonic speeds and can be equipped with at least four hypersonic stealth cruise missiles.

At the same time, China can use its nuclear power industry to support its nuclear weapons program. Last year, China planned to build 150 new nuclear reactors worth US$440 billion, which is more reactors than the rest of the world put together in the past 35 years. That said, it is highly likely that at least part of this infrastructure would be allocated to supporting China’s nuclear weapons program, analysts say.