America’s “No First Use” Nuclear Doctrine Debate: Implications for the Taiwan Strait

America’s “No First Use” Nuclear Doctrine Debate: Implications for the Taiwan Strait

America’s “No First Use” Nuclear Doctrine Debate: Implications for the Taiwan Strait

Writing in the last issue of the Global Taiwan Brief, I argued that Chinese nuclear strategy will be a key factor in shaping the likelihood and potential course of a conflict in the Taiwan Strait. I focused in particular on China’s “no first use” (NFU) policy—in which it pledges not to use nuclear weapons first—the content and fate of which will influence outcomes in significant ways. China, however, is not the only country debating NFU. The United States is also engaged in a similar debate, which has potential implications for the Taiwan Strait and the broader Indo-Pacific region.

In April of this year, Senator Elizabeth Warren and Representative Adam Smith reintroduced the No First Use Act, which they had previously put forward in early 2019. With a past (and potential future) presidential contender and the chairman of the House Armed Services Committee having thrown their weight behind a US embrace of “NFU,” the debate over doing so is likely to persist. The adoption of an NFU policy would mark a profound change for US nuclear strategy.

The Case for “No First Use”

According to the joint Smith-Warren press release, adopting “no first use” would benefit national security by:

  • “Reducing the risk of miscalculation or misunderstanding by an adversary during a crisis that could lead to nuclear use;
  • “Strengthening our deterrence and increasing strategic stability by clarifying our declaratory policy;
  • “Preserving the US second-strike capability to retaliate against any nuclear attack on the US or its allies.”

Aspects of these claims have some merit. If rivals and adversaries are reasonably confident that the United States has no intention of using nuclear weapons first in a conflict, they are less likely to misinterpret American actions; less likely to raise their own nuclear alert levels; and, especially in the case of countries with smaller arsenals, less likely to embrace “use it or lose it” logic. As a result, the prospects for nuclear escalation in a conflict could be significantly reduced. This would, of course, be a positive outcome, but a shift to NFU could have significant negative repercussions as well.

American NFU and the Taiwan Strait

Despite the potential reduction in nuclear risk that would accompany a US shift to NFU, that shift could be dangerously destabilizing. In asserting that an American NFU policy would increase “strategic stability,” Warren and Smith perhaps mean that nuclear conflict would be less likely. The flip side of that coin, however, is that the risk of conventional conflict would go up.

The risk of nuclear escalation acts as an inhibitor for both the United States and its adversaries. Take away that inhibitor and the United States may be tempted to respond more assertively to relatively minor transgressions; and in Asia, China may be more tempted to opt for aggression in disputes with its neighbors. Indeed, an American NFU policy could significantly weaken Washington’s ability to deter China from using force against Taiwan. With reduced concern that the United States would resort to nuclear weapons in response to conventional attacks on US territory or in the event that Chinese victory looked likely, Beijing would be more confident in launching an assault on Taiwan in the first place.

America’s current nuclear strategy not only contributes to the deterrence of conventional conflict, but also may put guardrails on conflict when it does break out. Consider that Washington has successfully used that tool in the Taiwan Strait in the past, notably during the first and second Taiwan Strait crises of the 1950s. During the first crisis, in particular, President Eisenhower explicitly threatened to use tactical nuclear weapons against China. Mao ordered a halt to the shelling of Taiwan’s offshore islands two weeks later. During the second crisis, Soviet concerns over nuclear escalation had Khrushchev pleading with Mao to exercise restraint.

In a theoretical future scenario, having opted to invade or otherwise use force against Taiwan under circumstances in which the United States has adopted NFU, China may see less reason for caution in striking US bases on allied territory or on US territory itself in the event Washington decides to intervene on Taiwan’s behalf. An NFU policy—especially if mandated by law, as Warren and Smith propose—would deny the use of credible nuclear signaling as a tool for Washington to discourage Beijing from crossing certain lines.

The theoretical result, then, is a war that might have been averted with a different nuclear strategy and one that will be far more violent (at the conventional level) than it would have been even had deterrence failed. Such a war is also one that is more likely to touch the US homeland directly. Chinese cyber operations with the potential to have strategic effect—such as attacks on critical infrastructure or the financial system—may be more difficult to deter under circumstances in which American nuclear weapons are used exclusively to deter adversary nuclear use. The same is true for more indiscriminate attacks on US space assets, including satellites used for navigation, telecommunications, or weather forecasting.

It is, of course, possible to deter Chinese conventional, space, and cyber attacks in the midst of conflict with means besides nuclear weapons, but an NFU policy might hamstring Washington’s capacity to do so. The 2018 Nuclear Posture Review (NPR) put it this way: “Non-nuclear forces also play essential deterrence roles. Alone, however, they do not provide comparable deterrence effects, as reflected by the periodic and catastrophic failures of conventional deterrence to prevent Great Power wars throughout history.” It is, rather, the combined use of nuclear and non-nuclear forces that allow the United States to generate unique, robust deterrent effects. Again, according to the NPR:

US deterrence strategy has always integrated multiple instruments of national power to deter nuclear and non-nuclear attack. Integrating and exercising all instruments of power has become increasingly important as potential adversaries integrate their military capabilities, expanding the range of potential challenges to be deterred. This is particularly true of threats from potential adversaries of limited nuclear escalation and non-nuclear strategic attack.

Put simply, in adopting an NFU policy, the United States could make a Taiwan Strait conflict more likely, more violent, and more likely to involve (non-nuclear) attacks on the American homeland. This is presumably not the outcome that proponents of NFU have in mind.

Courting Proliferation

In the wake of an American shift to NFU, Taiwan might also find itself living in a region characterized by substantial proliferation pressures. Congressman Adam Smith argues that embracing NFU “would renew US leadership on nuclear nonproliferation and disbarment,” but American allies in Asia might not care much about American moral leadership if the price Washington pays for assuming that mantle is to undercut the security of its closest partners.

As noted above, the Warren-Smith press release indicated that their No First Use Act would enhance national security by “preserving the US second-strike capability to retaliate against any nuclear attack on the US or its allies.” But for those allies that count on US extended deterrence, this is hardly reassuring.  The proposed act has only one section, and that section comprises a single sentence: “It is the policy of the United States to not use nuclear weapons first.” Since they were already seeking to encroach on executive branch authority with this bill, and recognizing that American NFU would raise reasonable concerns among the allies, Warren and Smith could have taken the opportunity to explicitly define “first use” or codify the nuclear umbrella as well. Alternatively, they could have included “sense of Congress” language in the bill voicing continuing support for extended deterrence.  But they did not do so.

Were this bill ever to become law—or if a US administration were to shift to NFU on its own—Japan, South Korea, Australia, and other allies could be forgiven for concluding that the United States, in opting for greater restraint in its nuclear strategy, would sooner or later reassess its extended deterrence guarantees as well. They could likewise be forgiven for hedging against that possibility.

Indeed, despite the hopes of NFU advocates, an American NFU policy would contribute to conditions in Asia that are already increasingly conducive to a new wave of nuclear proliferation. Decisions by Indo-Pacific allies to develop their own nuclear weapons, moreover, could spell the end of the US alliance system in the region. Taiwan’s security would suffer as a result.

The main point: A future American “No First Use” nuclear policy could make a Taiwan Strait conflict more likely, more violent, and more likely to involve non-nuclear attacks on the American homeland. It would also make nuclear proliferation more likely in the Indo-Pacific region, to Taiwan’s detriment.