Russia’s leader Vladimir Putin unveiled several new nuclear weapons last week in a replay of the Cold War. China, meanwhile, is continuing a similar buildup of high-technology strategic nuclear forces that remains largely hidden from view.

Chinese secrecy about its nuclear forces and their use was a major theme of the Pentagon’s recently completed Nuclear Posture Review that outlined a new “tailored deterrence” policy for China.

The new plan is aimed at persuading Chinese leaders to avoid military miscalculations – like provocative actions in the South China Sea, or hostile activities related to Taiwan or Japan – that could quickly escalate into a nuclear exchange.

The unclassified posture review shed little light on the details of the buildup of China’s nuclear forces other than identifying what were called “entirely new nuclear capabilities.” They include several new types of missiles, including hypersonic weapons, satellite-killing missiles and regional intermediate-range nuclear forces.

The review takes note of the main threat of a nuclear war between the United States and China: A military encounter that escalates into a regional conflict culminating in a nuclear exchange involving China’s regional nuclear-armed missiles.

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“Our tailored strategy for China is designed to prevent Beijing from mistakenly concluding that it could secure an advantage through the limited use of its theater nuclear capabilities, or that any use of nuclear weapons, however limited, is acceptable,” the review states.

The Pentagon did not specify how tailored deterrence would work. It warned that the United States “will maintain the capability to credibly threaten intolerable damage as Chinese leaders calculate costs and benefits, such that the costs incurred as a result of Chinese nuclear employment, at any level of escalation, would vastly outweigh any benefit.”

Strategic military planning for China, however, would likely seek to put at risk what Chinese leaders hold most dearly: Continued rule by the Communist Party of China. Thus, U.S. tailored deterrence would involve signaling to the Chinese leadership that any future conflict would result in the destruction of the Chinese Communist Party, and its military arm, the People’s Liberation Army.

Robust security for Chinese leaders

Chinese leadership statements and military writings make clear China probably understands that strategy, and the military has invested heavily in defending Party leaders.

The PLA has built robust leadership security systems that include networks of underground escape and transit systems to be used by senior Party leaders in a crisis or conflict.

For example, the Zhongnanhai leadership compound in Beijing, where Party leaders live and work, includes a terminal for a large underground tunnel and rail system that runs to a major command center west of the city known as the Western Hills. From that command center, other underground trains and tunnels lead to additional secure facilities in various parts of the country.

Unfortunately for the Chinese, U.S. intelligence agencies have known the locations of many of these leadership protection facilities. And the Pentagon has been developing precision-guided bombs and missiles capable of penetrating the underground bunkers and tunnels – putting China’s most valuable strategic assets at risk.

Beijing refuses to discuss its nuclear policies

One problem for the United States has been China’s repeated refusal to engage in official discussions that could make such deterrence goals clear.

“We have long sought a dialogue with China to enhance our understanding of our respective nuclear policies, doctrine, and capabilities; to improve transparency; and to help manage the risks of miscalculation and misperception,” the review says. “We hope that China will share this interest and that meaningful dialogue can commence.”

The reason China does not hold such talks is the Chinese view that any discussion of its strategic nuclear and non-nuclear capabilities – such as nuclear forces, space weapons and cyber-attack capabilities – as undermining deterrence.

That was disclosed several years ago in a classified State Department cable outlining a June 2008 meeting in Beijing. During the talks, U.S. officials called on China to be more open about its nuclear capabilities.

In response, China’s then-Assistant Foreign Minister He Yafei responded that China’s nuclear forces were a “sensitive issue” and officials engaged in the talks did not even know the size of China’s nuclear arsenal. “Now is not the time for China to tell others what we have,” He Yafei said, adding that even revealing the size of the nuclear arsenal would “eliminate its deterrent value.”

Thus, excessive secrecy remains a hallmark of China’s approach to deterrence. By keeping its nuclear and non-nuclear military power secret, China calculates the United States will not risk a conflict without fully knowing what kind of weapons will be used.

The Pentagon’s new posture review, however, appears to be taking the Chinese strategic secrecy into account.

Pentagon expanding conditions for using nukes

Because China is developing new and formidable capabilities to threaten U.S. interests and those of allies and partners, the Pentagon is expanding the conditions for using nuclear forces in response to non-nuclear attacks, such as the destruction of satellites or devastating cyber attacks on power grids.

“The United States is prepared to respond decisively to Chinese non-nuclear or nuclear aggression,” the review says.

While continuing to seek “meaningful dialogue” with China, the United States will use military exercises that demonstrate nuclear strike capabilities, and, second, will increase the range of “graduated nuclear response options available to the president,” the review said.

China’s Defense Ministry reacted to the nuclear review with harsh criticism. Spokesman Ren Guoqiang, repeating standard Beijing propaganda, saying the review’s view of China as a threat was a reflection of American anti-communism.

“We hope the US side will discard its ‘cold-war mentality,’ shoulder its own special and primary responsibility for nuclear disarmament, understand correctly China’s strategic intentions and take a fair view on China’s national defense and military development,” he said.

American defense officials say the secret version of posture review includes details on the weapons of concern, including the growing arsenal of land-based missiles of various types and ranges, and the addition of multiple warheads that are both independently targetable and maneuverable.

China’s vast underground tunnel network

The secret review also addresses the numerous unknowns about China’s nuclear modernization program, such as total warheads in the stockpile, their location in the 3,000-mile long underground tunnel network known as the Great Underground War, and uncertainties about the chain of command and decision-making for using nuclear arms.

Most American intelligence analysts and military planners doubt the official Chinese declaratory policy of not being the first nation to use nuclear weapons in a conflict.

“While China’s declaratory policy and doctrine have not changed, its lack of transparency regarding the scope and scale of its nuclear modernization program raises questions regarding its future intent,” the review states.

All signs related to the Chinese nuclear buildup, especially the increase in both numbers and capabilities for short- and medium-range nuclear missiles, suggest Beijing is preparing to use its nuclear arsenal during the early phases of a conflict and not after a nuclear strike on China.

Like the United States, China appears to be planning to blend nuclear and conventional military power in tandem.

China, Russia increased nukes while US cut back

Thus, nuclear explosions in space designed to knock out U.S. intelligence, surveillance, reconnaissance and command and control systems could be a first use of nuclear arms early in a conflict.

Once satellites have been disabled, China’s formidable cyber forces would go to work attacking critical infrastructure, including attacks on the U.S. electric grid.

The review also accuses China of exploiting American nuclear weapons restraint, which took place during the administration of President Barack Obama when nuclear weapons were downgraded in U.S. defense strategy. While the US reduced nuclear arms, China and Russia both “moved in the opposite direction,” the review states.

Beijing’s nuclear build-up

The nuclear buildup is a central part of what Chinese supreme leader Xi Jinping has announced the PLA will fully modernize by 2050. The weapons include a new road-mobile strategic intercontinental ballistic missile (ICBM), a new multi-warhead version of its DF-5 silo-based ICBM, and its most advanced ballistic missile submarine armed with new submarine-launched ballistic missiles (SLBM).

A new bomber is also planned that would provide Beijing with a complete nuclear triad.

The intermediate-range DF-26, a missile with precision guidance, is also one of the major strategic nuclear missiles that can strike both land and naval targets.

A further indication of China’s growing strategic offensive capabilities is the development of Chinese missile defenses.

While Beijing routinely criticizes American homeland missile defenses as destabilizing, China is secretly building two types of long-range missile defenses, a new mid-course defense against incoming ICBMs along with a sea-based mid-course defense and theater ballistic missiles defenses.

The new US deterrence policy is likely to remain wrapped in secrecy unless China changes its policy of not engaging in strategic talks with the United States.

This article originally appeared on Asia Times.