Why ‘Strategic Ambiguity’ Trumps ‘Strategic Clarity’ on Taiwan

Arleigh-burke-class guided-missile destroyer USS Kidd transits the Taiwan Strait on 27 August 2021. Courtesy of US Department of Defense

When saying less about the defence of Taiwan is more.

Asked during a ‘town hall’ event in Baltimore on 22 October whether the US would defend Taiwan if it was attacked by China, US President Joe Biden stated, ‘Yes, we have a commitment to do that’. Some see this as a welcome step to frame US policy vis-à-vis Taiwan through ‘strategic clarity’ rather than the ‘strategic ambiguity’ that has defined it for decades. For others, however, ‘strategic clarity’ is unnecessarily provocative, as it would effectively extend a security guarantee over a territory that Beijing views as an ‘integral’ part of the ‘motherland’, and militarily unsound given wargaming that shows US forces suffering significant losses in a potential war over Taiwan.

The crucial issue here is a disjuncture between the moral grounds for adopting less ambiguous commitments to Taiwan and the continuing strategic utility of ambiguity if the core US objective is avoiding war with China. Put simply, while a clear statement that the US is committed to the defence of Taiwan on the grounds that only the people of Taiwan should decide its future is both morally sound and politically attractive, it does not resolve the dilemma that some of its advocates believe it will – i.e., enhancing the credibility of US deterrence vis-à-vis China.

This is because greater certainty regarding US intentions and ‘red lines’ is not what has kept a lid – however imperfectly – on this potential flashpoint. Rather, as Thomas Schelling observed, central to the operation of deterrence is the manipulation of risk or uncertainty. For deterrent threats to be credible, they ‘do not need to depend on a willingness to commit anything like suicide in the face of a challenge’ but rather must carry the risk that the deterrer ‘is likely to do something that is fraught with the danger of war’ through a ‘compounding of actions and reactions, calculations and miscalculations, of alarms and false alarms, of commitments and challenges’. A country, he observed, could credibly ‘threaten to stumble into a war even if it cannot credibly threaten to invite one’.

‘Strategic Ambiguity’: Flawed but Effective

Despite President Biden’s assertion, it is clear that the US does not currently have a commitment to defend Taiwan in the event of a Chinese attack. Since the formal normalisation of Sino-US relations in 1979, Washington’s position vis-à-vis Taiwan has been guided by the Taiwan Relations Act (TRA). The TRA asserted that while Washington had determined to recognise the People’s Republic of China (PRC), it is the policy of the US:

  • To preserve and promote extensive relations with the people of Taiwan.
  • That peace and stability in the area are in the political, security and economic interests of the US.
  • That establishment of relations with the PRC rests upon the expectation that the future of Taiwan will be determined by peaceful means.
  • That any effort to determine the future of Taiwan by other than peaceful means would constitute a threat to the peace and security of the Western Pacific area and be of grave concern to the US.

As a result, the TRA identifies the need ‘to provide Taiwan with arms of a defensive character’ and ‘to maintain the capacity of the United States to resist any resort to force or other forms of coercion that would jeopardize the security, or the social or economic system, of the people on Taiwan’.

The resting of post-1979 policy on the basis of ‘strategic ambiguity’ has successfully attenuated the risk that Washington could become entrapped in a war with China over Taiwan

While successive US administrations since 1979 have utilised the TRA to provide Taiwan with access to significant military capabilities, none has ever provided a definitive statement that Washington would in fact use its military ‘capacity’ to defend Taiwan. The Taiwan Strait crises of 1954–1955 and 1956–57, for instance, had demonstrated the very real risks to the US of too overt a commitment to the defence of Taiwan.

The resting of post-1979 policy on the basis of ‘strategic ambiguity’ – i.e., ensuring that neither Beijing nor Taipei can be certain of US involvement in the event of a cross-Strait conflict – has successfully attenuated the risk that Washington could become entrapped in a war with China over Taiwan. The success of ‘strategic ambiguity’ has also been underpinned by the fact that for much of the time since 1979 China did not possess the military capabilities to directly or indirectly coerce Taiwan.

Despite this, some administrations have come closer than others to making a break from ‘strategic ambiguity’ since 1979. For instance, in April 2001 President George W Bush asserted in the wake of his decision to approve a US$5 billion arms sale package to Taiwan – including submarines and Kidd-class destroyers – that the US would do ‘whatever it took’ to defend Taiwan. Bush nonetheless moderated this position and sought to discourage Taiwanese moves toward a referendum on independence in order to pursue greater engagement with Beijing.

The Drumbeat of ‘Strategic Clarity’

However, Biden’s unscripted remark is a further example of growing sentiment in the US over the past four years that Beijing’s efforts to directly and indirectly coerce Taipei require clearer statements of US support for Taiwan.

Under the administration of Donald Trump, for instance, there were a number of developments in this direction. These included: the Taiwan Travel Act of March 2018 that permits US officials to travel to Taiwan and meet with Taiwanese counterparts; the Taiwan Allies International Protection and Enhancement Initiative (TAIPEI), designed to assist Taiwan in maintaining existing diplomatic relations; and the passing of the National Defense Authorization Act (2020) that affirmed that the US would ‘strengthen defense and security cooperation with Taiwan to support the development of capable, ready, and modern defense forces’.

Meanwhile, Republican lawmakers introduced Taiwan-specific bills in both the Senate in 2019 (Taiwan Defense Act) and the House of Representatives in 2020 (Taiwan Invasion Prevention Act). The former would require the Pentagon to submit to Congress an annual report on the progress of ‘improving the ability of the U.S. Armed Forces to conduct combined joint operations to deny the ability of China to execute a fait accompli against Taiwan’, while the latter would authorise the president to ‘use the Armed Forces to defend Taiwan against a direct attack by China's military, a taking of Taiwan's territory by China, or a threat that endangers the lives of civilians in Taiwan or members of Taiwan's military’.

Many of the US’s security partners have long relied on 'strategic ambiguity' to hedge against being required to make firm commitments to back the US in the event of future hostilities with China over Taiwan

The strategic case for such ‘clarity’ regarding US commitments to Taiwan’s defence, according to advocates, is straightforward: ‘the odds of a Chinese blockade, missile strike, or invasion grow with each passing year’ and therefore only a clear and definitive statement of US intention and resolve will ‘dissuade’ China from ‘miscalculation’.

But is this really the case?

The Philippines and Japan, for example, which both have mutual defence treaties with the US, have confronted ongoing coercive challenges from Beijing in the South China Sea and the Senkaku Islands, respectively. In each case, ‘US clarity actually makes it easier for China to carry out its provocative acts of aggression’ as each state’s treaty with the US ‘lets China know what it can and cannot do’ and ‘enables China to locate and then define the boundaries of US action via constant testing of them’.

‘Strategic Clarity’ and US Integrated Deterrence

In addition to marking out the lines for US action, the new push for ‘strategic clarity’ has implications for US allies, especially in terms of the US emphasis on ‘integrated deterrence’, which seeks to bind its security partners more closely to US strategic planning through high-level integration and interoperability. Yet many of the US’s security partners have long relied on ‘strategic ambiguity’ to hedge against being required to make firm commitments to back the US in the event of future hostilities with China over Taiwan.

And whereas some keen US allies – like Australia, for instance – are likely to welcome the twin development of clear expectations and clear red lines, other regional actors would likely prefer the continued flexibility that strategic ambiguity confers, rather than having to accept the entrapment risk that comes along with networked integration and access to top-line US defence technology.

Put simply, this is because raising expectations on allies has a bifurcating effect. For the US, this may well make alliance management simpler. But it also constrains choice for its partners, which often have to juggle complex relationships with other regional stakeholders as well as domestic public opinion, in democratic as well as semi-authoritarian states.

In an era where the US will need to build complicated networks of allies to counter Chinese behaviour, the Biden administration runs the risk of narrowing its pool of potential partners

For instance, it would be difficult to imagine Singapore, Indonesia or even the US’s Quad partner India being comfortable providing anything more concrete than diplomatic support over a US–China conflict in Taiwan. And in an era where the US will need to build complicated networks of allies to counter Chinese behaviour, the Biden administration runs the risk of narrowing the pool of potential partners to those who could already have been counted on to support it militarily in any case.

‘Strategic Ambiguity’: The Least Bad Option

As two Taiwanese analysts have recently noted, ‘strategic ambiguity’ is not an end in itself, but rather is designed ‘to encourage a convergence of cautious and cooperative policies from Beijing and Taipei’ through a ‘dual deterrence’ of Chinese ‘aggression’ and Taiwanese ‘provocations’ toward independence.

Advocates of ‘strategic clarity’ point out that each aspect of this equation has now shifted. China’s military modernisation – including significant investment in anti-access/area denial capabilities – has overcome the historical weakness of its conventional capabilities vis-à-vis the US and Taiwan, while its use of ‘grey zone’ approaches (such as its serial violations of Taiwan’s Air Defense Identification Zone) to erode Taiwanese resolve demonstrates its capacity to indirectly coerce Taipei. Meanwhile, the chances of ‘Taiwan initiating a conflict, as past American administrations might have worried about when the island was under one-party rule and China was poor and weak, are now vanishingly small’.

Ironically, Beijing’s strategy toward Taiwan is now arguably defined by its manipulation of the deterrence ambiguity that has previously served the US well. China has relied on the US being ‘reactive and risk-averse’ and has assumed that ‘the US will either establish clear escalation thresholds’ or ‘will try and defuse lower-level provocations from becoming larger conflicts it would rather avoid’.

However, the Biden administration’s jettisoning of ‘strategic ambiguity’ in favour of ‘strategic clarity’ will not necessarily resolve this dilemma. A definitive defence commitment to Taiwan ‘means not only what one is prepared to take a risk for’ – such as repelling a conventional invasion of Taiwan – but would also provide a clear signal as to ‘what one would ignore’, further opening the potential for Beijing to pursue ‘grey zone’ strategies against Taiwan. ‘Strategic clarity’ could therefore undermine deterrence by decreasing the number of situations in which Beijing would have to run the risk that the US would do ‘something that is fraught with the danger of war’.

The views expressed in this Commentary are the authors’, and do not represent those of RUSI or any other institution.

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