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In the event of an armed conflict across the Taiwan Strait, does Taipei have a role to play in shaping nuclear dynamics amongst the major powers? A key concern for Taiwan’s political and military leaders is whether the United States will come to their aid in the event China opts to use force. Even if Taiwan can hold out for the days and weeks it will take the United States to mobilize—politically and militarily—for a fight with China, intervention is no sure thing. One important reason Washington might opt not to get directly involved is that in doing so, it will incur a risk of nuclear escalation. But by investing in conventional counterforce capabilities, Taipei may be able to alter the calculus in Washington and Beijing in way’s conducive to Taiwan’s interests.

China has long abided by a no first use policy. It has said it will never use nuclear weapons first, will never use nuclear weapons against non-nuclear states, and will only use nuclear weapons after first being struck. It has, moreover, stuck to a policy of what some scholars call “assured retaliation.” China scholars M. Taylor Fravel and Fiona Cunningham, leaders in the field, described it this way:

“This strategy uses the threat of inflicting unacceptable damage in a retaliatory strike to deter an adversary from attacking first with nuclear weapons. That is, following a first strike, China would still have enough weapons to retaliate and impose unacceptable damage on its adversary.”[1]

“Unacceptable damage” has typically been understood to mean strikes on a handful of American cities. This is a relatively restrained approach to nuclear use and, for several decades, there was good reason to believe it would hold in the event of a major crisis. Going forward, US strategists can longer be so confident that is the case.

Generally speaking, there are two reasons for this. First, over the last decade or so, there has been an open debate within China about whether the country’s nuclear doctrine needs updating. Some have argued that no first use should be relaxed, others that Beijing should adopt a broad definition of what constitutes a first strike against China, and others that nuclear weapons should be used to deter the use of conventional force (rather than only nuclear use). To be clear, there has been no formal change to Chinese doctrine, but that this debate was allowed to proceed is notable. It suggests that Chinese leadership may be less firmly committed to the stated doctrine than it has been in years past and hints that formal changes could be in store in the years to come.

The debate also reinforces a question that has certainly long nagged American leaders: if China were poised to lose a war with the United States over Taiwan’s fate—a loss that could come with severe repercussions for the Chinese leadership’s grip on power—would Beijing eschew nuclear threats or the use of nuclear weapons if it assessed such a move could change the course of the conflict?

Also raising doubts in the United States about China’s commitment to its stated doctrine is an emerging doctrine-capabilities gap. Investments in first strike capabilities, early warning radar, dual-capable intermediate-range missiles, and a far larger nuclear stockpile (DIA has assessed it will double within ten years) all point to a potentially far less restrained Chinese approach to nuclear use in the future. China’s strategic forces are, for the time being, arguably consistent with doctrine, but there is reason to believe that will not remain the case in the decade to come.

Put simply, while it is difficult to imagine the United States going nuclear first in a Taiwan Strait scenario, it is getting easier to imagine China doing so. That is a problem for Taiwan, as it makes US intervention less likely. But is it a problem that Taipei can mitigate?

One option would be for Taiwan to invest in a conventional, counterforce capability. In particular, Taiwan could consider developing the means to eliminate China’s silo-based intercontinental ballistic missiles (ICBMs). China only has 20 such missiles: 10 single-warhead DF-5As and 10 DF-5Bs, which can carry three warheads each. (China is also considering silo-basing for its DF-41, its newest, longest-range ICBM, but it is as yet unclear whether it will do so and, if so, in what numbers.)

Neutralizing China’s silo-based ICBM force in the opening stages of a conflict would not eliminate the risk of nuclear escalation should the United States ultimately decide to intervene, but it could make rapid escalation less likely. Silo-based weapons are typically considered first-use weapons. Because they are immobile, they are vulnerable. And because they are vulnerable, they are susceptible to use-it-or-lose-it logic. That logic is even stronger for missiles fitted with multiple, independently targetable reentry vehicles (MIRVs), as China’s DF-5Bs are and as the DF-41s likely will be.

China’s mobile ICBMs and submarine-launched ballistic missiles will make American leaders nervous, as keeping tabs on them will be a challenge, but that mobility makes it easier for Chinese leaders to hold them in reserve. In other words, if Taiwan were to disable China’s silo-based ICBMs before US intervention, Beijing might paradoxically feel less pressure to go nuclear early after American forces join the fight.

Taiwanese conventional counterforce strikes on Chinese missile silos, moreover, would allow the United States to commit limited resources to tracking and, if necessary, targeting Chinese mobile missiles, thus reducing the threat those missiles pose to the United States.

Taken together, these two results—softening use-it-or-lose-it logic in Beijing and simplifying America’s potential counterforce mission—could make US intervention more likely.

This course of action is not without risks for Taiwan. As noted above, some of the debates within China in recent years have focused on how to define “first strike,” raising questions about how China would respond to conventional attacks on its nuclear forces or on critical infrastructure like the Three Gorges Dam. Would Beijing consider a conventional strike by Taiwan on Chinese ICBMs a “first strike” and consider responding with nuclear weapons? This seems unlikely in the case of Taiwan, which does not itself have nuclear weapons and which the PLA would be in the process of invading. [2] To the extent, moreover, that Beijing was attempting to positively shape the international narrative regarding its assault on Taiwan, nuclear use against non-nuclear Taiwan would be, to put it mildly, counterproductive.

China might also consider responding to Taiwan’s counterforce strikes by launching a nuclear strike on the United States, perhaps assuming some level of coordination (and thus considering Washington the responsible party) and seeking to deter active US intervention in the conflict. But in doing so, Beijing would sacrifice any claim to the moral high ground in the court of public opinion and would invite US nuclear retaliation.

Concerns over the role of nuclear weapons in a cross-Strait conflict might lead Taiwan to consider fielding its own nuclear weapons, but doing so might well make Taiwan less secure. First, the United States is less likely to feel compelled to come to Taiwan’s aid if it abandons its commitment to nonproliferation. Washington, moreover, will be far less likely to intervene in a conflict with multiple nuclear weapons states, each with a different threshold for nuclear use. Nor should Taipei consider nuclear weapons as a guarantee against Chinese use of force. Indeed, a perceived need to disarm Taiwan could well prove a casus belli for Beijing.

Whether Taiwan should pursue an indigenous counterforce capability, as posited here, requires more study. Additional analysis may well lead to a conclusion that it would be destabilizing. But, going forward, the role of nuclear weapons in a Taiwan Strait crisis needs far more consideration than it typically receives, at least in unclassified settings. Although Taiwan may often be seen as a passive “observer” vis-à-vis the potential nuclear aspects of a hypothetical conflict, Taipei does have agency. Further research should consider whether Taiwan can positively shape nuclear dynamics in the event that China one day opts for invasion.

The main point: The risk of nuclear escalation is one reason the United States might choose not to intervene in a Taiwan Strait crisis. Taiwan should consider whether it can shape nuclear dynamics in such a way as to make American intervention more likely.

[1] Fiona S. Cunningham and M. Taylor Fravel, “Assuring Assured Retaliation: China’s Nuclear Posture and U.S.-China Strategic Stability,” International Security 40, no. 2 (Fall 2015): 13.

[2] Taiwan once had a clandestine nuclear weapons program, which was shuttered in the late 1980s. See, for example, David Albright and Andrea Stricker, Taiwan’s Former Nuclear Weapons Program: Nuclear Weapons On-Demand (Washington, DC: Institute for Science and International Security, 2018).