The “One China” Framework at 50 (1972–2022): The Myth of “Consensus” and Its Evolving Policy Significance

Abstract This lead article surveys the history and evolving policy legacies of the “one China” framework 50 years after US President Richard Nixon's historic 1972 visit to China. It begins by introducing key concepts and highlighting the crucial difference between Beijing's self-defined “one-China principle” and the US's, Japan's and key other countries’ variable “one China” policies as it relates to Taiwan. It argues that three seminal 1970s developments consolidated the “one China” framework as an informal institution of international politics. The ambiguity baked in by Cold War-era geopolitical necessity provided flexibility sufficient to enable diplomatic breakthroughs between erstwhile adversaries, but also planted seeds for deepening contestation and frictions today. Recent developments – especially Taiwan's democratization and Beijing's increasingly bold and proactive assertion of its claim to sovereignty over Taiwan – have transformed incentive structures in Taipei and for its major international partners. The net effect is that the myth of “consensus” and the ambiguities enabling the framework's half-century of success face unprecedented challenges today.

Fifty years ago, on 21 February 1972, US President Richard Nixon arrived in mainland China for a week-long visit intended to accelerate rapprochement with the communist-led People's Republic of China (PRC, hereafter also referred to as China) and to enable late-Cold War strategic realignment against the Soviet Union. This "week that changed the world" and the landmark "Shanghai Communiqué" signed during Nixon's visit enabled a historic US-China partnership after two decades of acrimony and set Washington on a path towards ultimatelyin 1979severing formal diplomatic ties and its 25-year-old mutual defence pact with the Republic of China (ROC, hereafter also referred to as Taiwan), withdrawing US military forces from Taiwan, and recognizing the PRC as the "sole legal government of China." Notably, however, in the 1979 US-PRC normalization communiqué, Washington did not recognize Beijing's position on "one China," an essential component of which is its claim that Taiwan is a PRC province. Rather, it merely "acknowledge [d] the Chinese position that there is but one China and Taiwan is part of China." 1 Of particular note in this context is that, regardless of Beijing's claim or the US position, since its establishment in October 1949 the PRC has never actually governed Taiwan.
Nixon's announcement the previous July of his forthcoming China trip had transformative effects internationally. In effect if not necessarily intent, it facilitated the October 1971 United Nations (UN) vote that granted Beijing "China's" seat. It also precipitated a cascade of foreign governments switching diplomatic recognition from Taipei to Beijing. Among these, most significantly for Taiwan, in September 1972, Kakuei Tanaka, prime minister of Japan, then the world's second-largest national economy, a US treaty ally hosting tens of thousands of US forward-deployed military forces close to the Taiwan Strait, and a key partner of Taipei itself, would travel to Beijing to establish diplomatic relations with the PRC, thus effectively ending Japan-ROC official ties. Together, Nixon's and Tanaka's 1972 visits to China augured a two-decade "golden age" in US-Japan-PRC economic cooperation and strategic alignment, significantly contributed to China's post-1978 "rise," and reshaped both the Cold War in Asia and international politics more generally. 2 Crucially, however, even after recognizing Beijing as China's "sole legal government," neither Tokyo nor Washington recognized the PRC's claim of sovereignty over Taiwan. Furthermore, both insisted on maintaining practically significant, if "unofficial" and "non-governmental," engagement with Taipei thenceforth. As these two critical cases show, and despite Beijing's increasingly proactive assertions to the contrary today, there has never been a universal consensus about what "one China" means, either in theory or in practise. Five decades later, much remains unsettled and in flux, with continuing and profound consequences for China's foreign relations, Taiwan, East Asia and the world.
Over the half-century since "the week that changed the world," the unresolved nature of the cross-Strait dispute over Taiwan's sovereignty and Beijing's all-butguaranteed pushback against any perceived challenge to its self-asserted "one-China principle" ( yige Zhongguo yuanze 一个中国原则)i.e. Beijing's position that "there is only one China in the world, Taiwan is a part of China, and the government of the PRC is the sole legal government representing the whole of Washington and Tokyo -Beijing's and Taipei's two most important international partners after 1972powerfully consolidated the ambiguities about Taiwan's status at the heart of the framework. A third section briefly analyses the "one China" framework's practical implications for international politics between the 1970s and today, highlighting the importance of analytically differentiating Beijing's self-defined, self-asserted "one-China principle"especially its essential claim of PRC sovereignty over Taiwanfrom many foreign governments' variable and dynamic "one China" policies. A penultimate section examines how contemporary strategic, political and other vicissitudes both across the Strait and beyond present the framework's continued viability with more serious challenges today than at any point in the past 50 years. A final section concludes.

What the "One China" Framework Is and Why It Matters
The "one China" framework, as used herein and across this special section, denotes a tacit understanding in the international community that allows foreign governments to maintain formal, diplomatic relations with the PRC while also enjoying nominally "unofficial" or "non-governmental"but, in several significant cases, deeply substantiveties with Taiwan. The framework effectively creates a grey area that enables other states to recognize the first of two claims essential to Beijing's self-defined "one-China principle"that the PRC is China's "sole legal government"but avoid taking a position on the second -Beijing's assertion that Taiwan is a PRC province and therefore should be denied international status as a separate entity able to, inter alia, freely join most international organizations or sign treaties. Critically, the bounds of the grey area, and therefore the framework's flexibility, are contested and politically contingent. Thus, though Beijing demands all foreign governments recognize PRC sovereignty over Taiwan, it may refuse to do so. And Beijing has grudgingly tolerated the ambiguous status quo with numerous countries for decades. As discussed below, the US and Japan are particularly significant cases in point.
The inherent vagueness and flexibility at the heart of the "one China" framework, and the policy variability and dynamism enabled by it, have had profound practical consequences over the past half-century. On the one hand, the framework facilitated first the rapprochement and then extensive practical cooperation after 1972 between erstwhile adversaries (especially the US and China) that had long been at intractable loggerheads regarding key issues related to Taiwan. It also enabled considerable variation in its effective manifestation and operationalization across and within cases (including the Taiwan Strait itself) that, among other things, kept the peace and enabled Taiwan to persist as a de facto autonomous international political actor, maintain extensive and robust, if unofficial, ties with many of the world's most powerful democracies and advanced economies, thrive economically and, eventually, democratize. On the other hand, as discussed in this article's penultimate section, the vagueness and flexibility at the heart of the post-1970s "one China" framework also planted the seeds for the considerable frictions unfolding across and beyond the Strait under very different circumstances today.
Indeed, another recurring theme since the 1970s is that despite its grudging tolerance in practise, Beijing has often signalled that it will punish behaviour it perceives to be violating its self-asserted "one-China principle." In the interest of maintaining relatively stable ties with Beijing, other actors often acquiesce, or at least concede the rhetorical initiative, to Beijing. It is thus helpful to understand the "one China" framework as what political scientists refer to as an informal institution: it defines the "rules of the game" which, though unwritten, shape "many of the 'real' incentives and constraints that underlie [leaders'] political behavior." 7 Any foreign government that crosses Beijing's elusive "red line" on Taiwan can expect some form of negative backlash, though the severity can vary widely for political reasons. Fears of harsh consequences often incentivize self-censorship in the international community and effectively constrain states' behaviour in response to or in anticipation of potential backlash from Beijing, regardless of countries' official positions on "one China." As discussed in the later section of this article on contemporary factors that challenge the framework today, the expanding scope of Beijing's proactive policing of its "principle" in recent years, including beyond the halls of international diplomacy, is an additional source of increasing friction.
Fifty years after Nixon's groundbreaking visit, recent real-world developments are raising serious questions about the framework's continued viability and, by extension, the sustainability of peace and stability across the Taiwan Strait. In this regard, China's growing power and intolerance for perceived departures from its self-asserted "one-China principle"; Taiwan's robust democratization, together with the US's and other major democracies' manifest desire to deepen practical support for Taiwan's effective autonomy in the face of deepening pressure from Beijing; and China's increasingly fraught relations with Washington and most major US democratic allies more generally conspire to present the extant "one China" framework with perhaps its greatest challenge of the past half-century.
The Origins and Consolidation of the "One China" Framework in the 1970s The dispute over "one China" emerged internationally in the aftermath of the Chinese Civil War when, in 1949, the KMT (Kuomintang, or Chinese Nationalist Party) was defeated by the Chinese Communist Party (CCP) and fled to Taiwan. The KMT set up a "provisional" capital in Taipei for the extant ROC regime. Meanwhile, the CCP established the new PRC capital in Beijing that October. The PRC coined the term "one China" ( yige Zhongguo 一个中国) in the mid-1950s because of suspicions that US containment strategy vis-à-vis international communism meant Washington was plotting to establish Taiwan as a country independent of China. 8 Therefore, the genesis of "one China" was Beijing's direct opposition to what it called "two Chinas" (liangge Zhongguo 两个中国), where Taiwan would be recognized as a "second" China, or "one China, one Taiwan" ( yi Zhong yi Tai 一中一台), where Taiwan would be an independent country with no connection to the PRC or the ROC regime.
Between 1949 and 1991, the KMT/ROC regime in Taipei also rejected "two Chinas" to support its claim that the Chinese Civil War was not over. Internally, the ROC governmentcomposed mainly of "mainlander" elites who had fled to Taiwan in 1949maintained that Taiwan was part of Chinese (but not PRC) territory to justify its single-party government and to refuse popular elections on the island. Externally, the KMT regime wanted to prevent the CCP from succeeding in its effort to convince the international community that the PRC had succeeded the ROC as the government of China, and should therefore replace the ROC and represent "China" internationally (especially at the UN). 9 It was not until 1991, when the ROC government abolished the "Temporary Provisions Effective During the Period of National Mobilization for Suppression of the Communist Rebellion" (Dongyuan kanluan shiqi linshi tiaokuan 动员戡乱时期临时条款) as part of its rapid democratization, that the ROC formally renounced its claim of authority over mainland China.
The dispute over who represented "one China" internationally manifested most conspicuously in the PRC and ROC's zero-sum competition for diplomatic allies. Throughout the Cold War, and consistent with its own claim to represent "one China," Taipei refused to claim Taiwan as another sovereign China or as another state unaffiliated with the PRC or ROCeven when major countries (e.g. the US) appeared open to the option before 1972. 10 The consequences for Taiwan's international status of this shared opposition to "dual recognition" during the Cold War were profound. As noted above, US-PRC rapprochement helped mark the 1970s as a historic turning point: since then, more than 100 foreign governments have recognized the PRCwith 40 recognizing Beijing in the 1970-1973 period alone (see Figure 1). 11 Yet the practical significance of the "one China" issue after the 1970s transcends the quantitative matter of which "China" enjoyed official diplomatic recognition from more foreign governments. Fifty years after losing its UN seat, and although its most important international partners do not officially recognize it as a sovereign state, Taiwan continues to enjoy de facto international autonomy. To understand how this has been possible, it is important to briefly review how critical decisions made by Washington and Tokyo -Beijing's and Taipei's two most important international partners in the 1970sprofoundly affected 8 Huang 2001. 9 Liu 2001Rigger 2011, 137. 10 Tucker 2009, 17. 11 Xiu 2015 the meaning and practical significance of "one China" thenceforth. Crucially, though by the end of the decade both governments would ultimately sever diplomatic relations with Taipei, the ambiguity of their official positions on Taiwan's status and their evolving policies towards and support for it afterward were fundamental to consolidating the "one China" framework in international politics, with vagueness and flexibility at its heart.

The 1972 US-PRC Shanghai Communiqué
When in July 1971 Nixon announced his plan to make a historic visit to China the following year, Washington had never recognized the PRC regime and still maintained official relations and a mutual defence pact with Taipei. Therefore, one major precondition for Washington and Beijing to achieve mutually desired US-PRC rapprochement and strategic realignment against the Soviet Union was a modus vivendi on the question of Taiwan.
The critical issue Beijing sought to address was the US position on Taiwan's status vis-à-vis "China," which since the 1950 outbreak of the Korean War had been that it was "yet to be determined." During Henry Kissinger's secret trip to China in July 1971 to lay the groundwork for Nixon's future visit, PRC Premier Zhou Enlai 周恩来 demanded that Washington recognize the PRC as the sole legitimate government representing the Chinese people; recognize that Taiwan belonged to China; not support a "two Chinas" or a "one China, one Taiwan" policy, or the so-called Taiwan independence movement; and not assert its position that the status of Taiwan was undetermined. However, Kissinger did not commit to recognizing that "Taiwan belongs to China." 12 In the US-PRC joint communiqué the following year, often referred to as the Shanghai Communiqué, the PRC unilaterally reiterated Zhou's four requirements, while Washington adopted the "acknowledge" and "does not challenge" formula regarding the PRC's position on Taiwan's status.
Meanwhile, Washington pushed Beijing to commit to resolving cross-Strait disputes peacefully. Beijing resisted adamantly, asserting that the Taiwan question was a matter of PRC sovereignty and thus an "internal affair." In the Shanghai Communiqué, Beijing stated (unilaterally) that "the liberation of Taiwan is China's internal affair in which no other country has the right to interfere," while Washington "reaffirm[ed] its interest in a peaceful settlement of the Taiwan question." 13 As Romberg explains, what Beijing got from the Shanghai Communiqué, at best, was a US concession to not support either a "one China, one Taiwan" or "two Chinas" framework, or Taiwan's independence. However, this formula did not rule out the US potentially accepting either Taiwan's independence or unification. Rather, it committed Washington only to take a neutral position on the outcome, provided it was reached peacefully. 14 More importantly, though, around the time of Nixon's trip, Washington and Beijing faced international and domestic constraints that limited concessions each could make. 15 In the Shanghai Communiqué, the two sides cleverly adopted an "agree to disagree" format to circumvent these constraints. 16 This flexible approach reflected a lack of consensus on Taiwan, but nevertheless enabled them to reconcile their respective domestic needs and increasingly aligned strategic interests.
The 1972 Japan-PRC normalization communiqué, the "Japan formula" and the 1978 Treaty of Peace and Friendship After Nixon's 1971 announcement that he would visit China, Tokyo moved quickly to normalize relations. Initially, Beijing asserted that Tokyo would have to recognize its position that there is only one China and that the PRC is its sole legitimate government; that Taiwan is a province of China and an inalienable part of Chinese territory; and that the 1952 Japan-ROC peace treaty was "illegal." However, Japan's negotiators succeeded in getting Beijing to accept a normalization communiqué in which Tokyo only "recognize[d]" the PRC government "as the sole legal Government of China," while effectively circumventing Beijing's second and third conditions. 17 12 LRO 1997, 458, 467-468;Romberg 2003, 31-33. 13 AIT 1972. 14 Romberg 2003, 35. 15 Tucker 2001, 235, 255-256. 16 LRO 1997, 490-491. 17 He 2017 In short, Japan's official 1972 position on "one China" notes only that Tokyo "fully understands and respects" Beijing's stand "that Taiwan is an inalienable part" of PRC territory. 18 Significantly, Tokyo does not itself take a position on Taiwan's status. As Liff points out in this special section, this vague posture subsequently enabled Tokyo to carve out considerable flexibility concerning subsequent engagement with Taiwan, without violating any putative commitment to Beijing. Furthermore, under the precedent-setting "Japan formula," Beijing tacitly accepted Tokyo's unilateral assertion that Japan would maintain robust, if unofficial, ties with Taiwan, to include what many consider a de facto embassy in Taipei. Thus, the 1972 Japan-PRC negotiations resulted in two major outcomes foundational to the "one China" framework's subsequent consolidation and operation in international politics: Tokyo normalized diplomatic relations with the PRC despite not recognizing Beijing's claim of sovereignty over Taiwan, and it also insisted on maintaining practically significant, if unofficial, ties with Taipei thenceforth. 19 Amid perceived strategic necessity (read: containing Moscow) and Beijing's desire for massive US and Japanese economic cooperation as it launched "reform and opening up," this post-1972 status quo proved sufficiently tolerable to PRC leaders that they agreed not to even discuss Taiwan during negotiations over what would become the 1978 Japan-PRC Treaty of Peace and Friendship. (The treaty does not even mention "Taiwan." 20 ) This lack of contestation and the conspicuous absence of any reference to Taiwan in the second major political document defining Japan-PRC relations further established the 1972 normalization communiqué and Japan formula as institution-creating precedents whose vagueness, flexibility and lack of Japan-PRC consensus were fundamental to their viability. 21 Beyond their direct significance for Japan-Taiwan relations after 1972, these outcomes provided a direct model for Washington and several other countries. 22 The 1979 US-PRC normalization communiqué As US-PRC normalization negotiations shifted into higher gear under the administration of US President Jimmy Carter, US leaders eventually resigned themselves to abrogating the US-ROC Mutual Defence Treaty, withdrawing US troops from Taiwan, and severing diplomatic relations with Taipei. The fundamental issues regarding the US's vague official position on Taiwan's status and demand for the PRC to commit to a peaceful resolution, however, remained unsettled. Over years of negotiations, both aforementioned 1972 precedents (the US-PRC Shanghai Communiqué and the Japan-PRC normalization 18 MOFA 1972. 19 Liff, this issue. 20 PRC Ministry of Foreign Affairs 1978. 21 Liff, this issue. 22 Hirakawa 2006 communiqué) were repeatedly referenced as Washington and Beijing sought to accommodate each other's incompatible positions.
Eventually, the 1979 US-PRC normalization communiqué referred vaguely to the Shanghai Communiqué and contained no indication of the US position on Taiwan's status; it merely "acknowledge[d] the Chinese position that there is but one China and Taiwan is part of China." 23 The PRC vehemently objected to continued US arms sales to Taiwan. However, Washington would not budge on packaging the sale of defensive arms in its "full range commercial relations" with Taiwan to meet the island's legitimate security concerns. 24 Ultimately, the PRC allowed normalization to go forward but wished to address the arms sales issue later. 25 In another related development, under landmark US domestic legislation known as the 1979 Taiwan Relations Act (TRA), Washington made an ambiguous commitment to "consider any effort to determine the future of Taiwan by other than peaceful means…of grave concern," committed to selling "defensive" arms, and created a nominally private corporation (supported with government funding) to continue the US's "unofficial" presence in Taiwan. 26 In all three critical cases above, international and domestic political exigencies interacted to shape what was possible. They incentivized compromises between Beijing and its erstwhile early-Cold War adversaries that, though representing progress in principle, did not fundamentally resolve the issue of Taiwan's status. Nevertheless, vague concessions, compromise and flexibility worked into these agreements were sufficient to enable Beijing to agree to normalize diplomatic relations with both Tokyo and Washingtontransforming the Cold War and international politics and accelerating economic cooperation that would facilitate China's rapid post-1980s rise. Yet both Japan and the US also carved out space for maintaining substantive and robust, if officially unofficial, ties with Taiwan.
The idea of "one China" predated Nixon's historic visit to China. However, the combination of the PRC's admission to the UN that followed Nixon's announcement of his upcoming trip, the Shanghai Communiqué released during his visit, and both the terms under which Tokyo and Washington normalized official relations with Beijing (and chose to operationalize "unofficial" ties with Taipei thenceforth) marked the 1970s as a critical juncture in the "one China" framework's consolidation as an informal institution shaping China's foreign relations and international politics ever since. As the contributions to this special section demonstrate, even beyond the US case that has dominated the existing literature, the vagueness and flexibility at the heart of the framework have had profound real-world consequences for other parties' relations with Beijing (and Taipei) over the past 50 years.
The "One China" Framework as an Informal Institution in Practise since the 1970s The "one China" framework emerging from the 1970s developments discussed above reflects two political understandings widely shared in the contemporary international system. The first is that no foreign government can simultaneously recognize both the PRC/mainland China and the ROC/Taiwan as sovereign states. Instead, each must choose either Beijing or Taipei with regards to official diplomatic relations and representation of "China" in international organizations. 27 Importantly, the idea that there is (or can be) only "one China" has no basis in international law or treaty; 28 rather, it is an informal (and contested) political normone enforced internationally by both Beijing and Taipei throughout the Cold War, and Beijing exclusively after 1991.
Second, especially since the early 1970s, even after formally recognizing the PRC, there is considerable flexibility concerning whether, how and how extensively foreign governments choose to develop their "unofficial" relations with Taiwan. These bounds are amorphous, often unspoken and politically contingentand can vary considerably across cases and time. Most famously, Beijing tolerates levels of US engagement with Taiwan, including military cooperation and high-level dialogues, that it would (presumably) never allow in other cases. Furthermore, the breadth and depth of US-Taiwan cooperation, while nominally "unofficial," has varied significantly over time. Conversely, despite having an official position on "one China" similarly vague to its ally the US, since normalizing diplomatic relations with the PRC in 1992, South Korea has long avoided robust cooperation with Taipeipresumably because Seoul is more concerned than Washington about potential backlash from Beijing, either directly or in a manner that frustrates its efforts to address various concerns vis-à-vis North Korea. 29 The myth of "consensus" in practise: Beijing's "one-China principle" versus others' "one China" policies Though an essential implied manifestation of China's self-asserted "one-China principle"non-recognition of Taiwan as a sovereign stateenjoys basic conformance internationally (see Figure 1), 13 foreign governments and the Vatican do maintain official diplomatic ties with Taipei today. However, arguably of greater practical significance for Taiwan are two essential facts at the heart of the "one China" framework's effective operation in international politics over the past 50 years. First, major advanced democracies and some of the world's largest, most influential economies (including the US, Japan, the EU 27 Bush 2017, 8. 28 For example, UN Resolution 2758, which effectively granted the PRC "China's" seat at the UN does not mention "Taiwan" or the "Republic of China," much less does it say anything about the government's sovereignty or prospects for future participation in the UN. Drun and Glaser 2022. 29 Lee and Liff forthcoming. and other key US allies in Asia and Europe) recognize the PRC as the "sole legal government of China" but do not recognize Beijing's claim of PRC sovereignty over Taiwan. Most maintain ambiguous positions on Taiwan's status; others adopt none at all. Second, in practise, even after officially recognizing Beijing, many major democratic powers have developed robust, if nominally unofficial, ties with Taipei. The US is the most famous and practically significant example, but it is far from the only one. Other major powers, including Japan and the EU, adopt similarly vague positions and, especially in recent years, have increasingly pursued practical cooperation with Taiwan. 30 Nevertheless, despite the ambiguity embodied in the framework since the 1970s and the objective reality of key players' ambiguous official positions and practises on "one China," in recent years, Beijing has more boldly and proactively asserted that its "one-China principle" is a "basic norm of international relations and universal consensus in international society" (guoji guanxi jiben zhunze he guoji shehui pubian gongshi 国际关系基本准则和国际社会普遍共识). To exert control over the global narrative about "one China," Beijing strongly, albeit misleadingly, implies that the US, Japan and every other country that has normalized relations with the PRC has agreed to it. 31 It also retroactively and erroneously claims that UN Resolution 2758 means that UN member states have determined that Taiwan is part of the PRC. 32 In other words, Beijing today boldly asserts universality and implied equivalence between its "one-China principle" and other foreign governments' policies related to "one China" (i.e. their "one China" policies). The empirical reality, however, is far more complicated and variableboth across cases and within them.
Across this special section, we conceive of a foreign government's "one China policy" as basically encapsulating two factors: first, its official position on "one China" (read: Taiwan's sovereign status); and second, how the government chooses to operationalize that position in practical terms, i.e. the nature, degree and extent of effective engagement of, cooperation with and public support for Taiwan in the absence of formal diplomatic ties. 33 Though the phrase "one China policy" is often used in reference to the US, Washington is not alone in adopting positions and policies clearly inconsistent with Beijing's self-asserted "principle" and preferences.
The first factorthe government's official position on "one China"is usually, though not always, formalized in a joint political communiqué normalizing diplomatic relations with the PRC. As such, it is typically static. To be sure, some governments effectively adopt the PRC's language on "one China" verbatim, and 30 Drun and Glaser 2022. 33 In his study of US "one China policy," Bush notes this could also include the government's position on how cross-Strait differences should be resolved. Bush 2017, 18-22. there is little, if any, daylight between their official position on Taiwan's status and the PRC's. Other foreign governments, however, adopt either no position or an ambiguous one reflecting subtle, but significant, differences with Beijing's "one-China principle." 34 Examples of the latter group include not only the immensely consequential US and Japan but also other major US democratic allies.
As for the second factor, the empirical record also demonstrates considerable variability in how foreign governments choose to operationalize their official position in terms of practical policies and the nature and degree of engagement and cooperation vis-à-vis Taiwan. Excepting the "third rail" of official diplomatic recognition of Taipei, the bounds of what is possible policy-wise are ambiguous and shaped by domestic and international political factors. For example, today, Beijing effectively, if grudgingly, tolerates far greater support for and cooperation with Taiwan from Washington than it would (conceivably) ever brook from smaller, weaker powers. And though Seoul, Tokyo and Washington all adopt similarly vague official positions in their respective normalization communiqués with Beijing, their respective levels of practical engagement and public support for Taipei differ significantlywith Seoul by far the most reluctant to risk angering Beijing, and with Tokyo more willing but still not nearly as forward-leaning as its ally the US. 35 Indeed, as the US, Japan and other cases demonstrate, the manner in which governments choose to operationalize their vague position on Taiwan's statusif they even have onein policy terms can vary widelyboth across cases and even within them (i.e. changing over time). How leaders choose to interpret "unofficiality" is politically contingent. In analysis of the US case, for example, Bush notes four factors that affect US decision making: consideration of national interests, expected reaction from Beijing, Taiwan's own policies, and domestic political pressures. 36 The same generally applies in other cases as well.
The US example and beyond. The most famous and consequential manifestation of the aforementioned disconnect between Beijing's "principle" and another country's effective "policy" is the US's "one China policy," which is not defined in a single document, much less any agreement with Beijing. Rather, it is the effective culmination of decades of statements and policies, including not only the (non-binding) political communiqués that Beijing prefers to cite 37 but also domestic legislation (such as the 1979 TRA), 38 presidential statements (such as the recently declassified 1982 "Six Assurances") 39  As mentioned already, though the US's official (1979) position on "one China" recognizes the PRC "as the sole legal government of China," it does not recognize Beijing's claim that Taiwan is part of the PRC. More critically, though the US "does not support Taiwan independence," it asserts an interest in "maintaining strong, unofficial relations with Taiwan," adopts variable policies and rhetoric in support of Taiwan's effective autonomy and democracy, and insists on "the peaceful resolution of cross-Strait differences." Washington's operational mantra is that it "opposes unilateral changes to the [cross-Strait] status quo by either side, and encourages both sides to continue their constructive dialogue on the basis of dignity and respect." 41 Not only is US policy not based upon any consensus with Beijing on Taiwan's status, its vague 1979 position has allowed significant adjustments to how Washington operationalizes its "one China policy" in practiseoften in response to perceived increased pressure on Taipei from Beijing. For instance, recent years have witnessed unprecedently high-level dialogues and visits involving senior US officials and military officers, more frequent arms sales and more forward-leaning congressional legislation and government rhetoric in support of Taiwan's effective autonomy and expanding US-Taiwan cooperation. For example, in January 2021, the US State Department terminated unilateral, selfimposed restrictions on US government contacts with Taiwanese counterparts, the intent of which had been to make US-Taiwan ties appear less "governmental" or "official." 42 Importantly, Beijing's rhetoric belies tacit recognition of the lack of consensus, such as when it demands that the US carry out a "genuine" (zhenzheng 真正), as opposed to a "fake" ( jia 假), "one China policy." 43 In short, US "one China policy" has evolved significantly over the past 50 years, often in response to changing circumstances in Taiwan and across the Taiwan Strait, and without asking for Beijing's permission.
Though the US case is illustrative, the contributions to this special section move beyond it to explore the considerable variation internationally about what "one China" can mean in practise and how key governments choose to operationalize their actual policies towards Taiwan. The exercise is revealing of political contingency. The differences in effective policiesincluding among countries with similarly vague "non-recognition" positions vis-à-vis Beijing's "one-China principle"are practically significant. The US and its military and other connections to Taiwan remain an outlier case in crucial regards. Still, others line up along a continuum, with some meaningful shifts closer to Washington in recent years.
In this special section, Liff demonstrates how Japan's approach to Taiwan has evolved and how Japan and Taiwan's "unofficial" relations have deepened significantly over time, despite Tokyo's unaltered 1972 position on "one China." 44 Brown shows that since the 1970s, both the EU's and its member states' policies evince variable but increasing willingness to expand practical links to, and cooperation with, democratic Taiwan, especially in recent years. 45 Kastner et al. demonstrate cross-national variation in responses to Taiwan's effort to contribute to the global fight against COVID-19, including willingness to support Taiwan's participation in the World Health Organization (WHO). 46 Chen's analysis of cross-Strait vicissitudes further exposes the inherent subjectivity and contestation of the definition and operationalization of "one China." It also highlights how the effective "one China" positions and policies of many important international political actors have been, and will inevitably continue to be, powerfully affected by domestic debates within Taiwan about how to resolve its dispute with the PRC, as well as Beijing's response. 47 In sum, the meaning, significance and acceptability of Beijing's self-defined "one-China principle" have always been contested outside the formal boundaries of the CCP-administered territory. This complex reality belies the myth of "consensus" increasingly asserted by Beijing. There is no global agreement on the question of "one China," much less how it should manifest in terms of foreign governments' policies towards Taiwan.
The PRC has tolerated other countries' diverse, often ambiguous official positions on and operationalization of policies regarding "one China" only grudgingly. In practise, in recent years Beijing has increasingly used its various and expanding levers of influence to attempt to shape international public opinion and foreign governmental behavioursometimes coercivelytowards de facto conformity with "one China" as Beijing defines it. For instance, in 2021, after Lithuania allowed a "Taiwanese" representative office in Vilnius, Beijing downgraded diplomatic ties and engaged in various forms of economic coercion. 48 In the face of Beijing's threats to punish behaviour it perceives to be violating its self-defined "one-China principle," and in the interest of ensuring stable economic and other ties with the PRC, many governments have traditionally seen different interpretations of "one China" as potentially incendiary political conflicts to be avoided, rather than principled positions to be proactively defended. Romberg describes Beijing's and Washington's modes of operation on the "one China" issue as mirror images: since the 1970s, the US can quietly do more than it can openly say, while the PRC government feels it must openly say more, even if it actually does less. 49 One significant consequence is that Beijing's misleading narratives gain traction internationally, facilitating the PRC's effort to unilaterally claim international legitimacy for its "principle" and demand other actors 44 Liff, this issue. 45 Brown, this issue. 46 Kastner et al., this issue. 47 Chen, this issue. 48 Reuters 2021. 49 Romberg 2003 correct their "wrongs." As a result, the "one China" framework has worked as an informal institution in practise that, though unwritten, effectively constrains international actors' behaviouralbeit to varying degrees. The expanding scope of Beijing's proactive policing of its "principle" today manifests as yet another driver of intensifying political frictions with the US and many other democratic powers in Asia and Europe.

Contemporary Factors that Challenge the "One China" Framework Today
With the benefit of a half-century's hindsight, the 1970s' strategically and economically expedient ambiguity that enabled extensive trilateral cooperation among Washington, Tokyo and Beijing in the late Cold War also planted seeds for the worsening contestation and frictions manifesting under very different circumstances today. By the 1990s, the shared Soviet threat that brought them together had evaporated. Furthermore, Taiwan's rapid democratization unleashed long-repressed voices that transformed cross-Strait dynamics and global democracies' interest in supporting the island. More recently, the US's and its allies' perceived strategic (and to a growing extent economic) interests appear increasingly at odds with a vastly more powerful and assertive China. The combination of deepening contestation within democratic Taiwan over its relationship with Beijing, shifting geopolitical winds, and major democracies' concerns that authoritarian China poses severe challenges to shared interests have transformed the context in which the "one China" framework operates. One recent consequence is that the US and key allies in Asia and Europe appear eager to significantly deepen symbolic and practical support for and cooperation with Taipei.
Exacerbating extant frictions is what appears to be an increasingly assertive PRC campaign to conflate other countries' nuanced or vague official positions on "one China" with Beijing's "one-China principle." As noted above, from individual country cases to the UN, Beijing unilaterally and often misleadingly asserts that an international "consensus" on Taiwan's status exists, aiming to squeeze the grey area in which other countries operationalize their practical relations with Taipei. In key instances, foreign governments have openly pushed back. 50 Flexibilities in the 50-year-old "one China" framework are now enabling these two conflicting developments simultaneously. The net effect is that, though the ambiguity at the heart of the framework has so far proved resilient, the very vagueness enabling its extraordinary success in the late 20th century now allows conditions that present major stress tests for its continued viability in the 21st.

Taiwan's democratization and deepening contestation across the Strait
Between 1949 and 1991, the cross-Strait dispute over "one China" was about whether the PRC or ROC represented China's "legitimate" government. It was largely contested between two authoritarian regimes dominated by men born in mainland China. In contrast, as explored by Chen's and Lin's contributions to this special section, Taiwan's democratization and generational change have transformed cross-Strait dynamics, introducing greater complexity and contestation over the idea of "one China," both within Taiwan and across the Strait. These cross-Strait vagaries are shaping and shaped by worsening geopolitical frictions between Beijing and other major powers and evince profound consequences for international politics more generally. 51 Most prominently, Taiwan's democratization has empowered long-oppressed voices advocating positions that Beijing sees as a threat to the very idea that Taiwan is a part of China. Because most people in Taiwan probably never shared the Cold War-era authoritarian KMT regime's dream of "retaking" or "reunifying" with the mainland, 52 Taiwan's democratization has allowed various sentimentsincluding some that are unambiguously pro-independenceto transform political discourse and representation (and leaders' electoral incentives) on the "one China" issue. Today, the vast majority of people in Taiwan support the status quo of effective autonomy, and extremely few support "unification." Against this changing domestic political backdrop, even some KMT leaders appear to be reconsidering the party's past stances. 53 Thus the ROC's official 1991 renunciation of its intent to compete with the PRC to represent China internationally did not resolve the dispute over "one China." On the contrary, Lin argues that it merely transformed the dispute from one of indivisible sovereignty more susceptible to escalation to what international relations scholars call a "commitment problem." Taiwan's democratization and Taipei's renunciation of its intent to "retake" the mainland have effectively removed this indivisibility issue but made Beijing doubt Taipei's commitment to stay connected to "China." Meanwhile, Taipei doubts Beijing's commitment to respect its people's will in settling the "one China" issue. This dynamic leads Beijing to judge that it cannot renounce the threat of force, while Taipei feels it cannot renounce the possibility of a de jure independence. 54 Understanding these dilemmas is essential to both cross-Strait and international efforts to keep the peace and promote stable and constructive ties.
In her contribution, Chen demonstrates how positions on "one China" differ among the three key political players across the Taiwan Straitthe CCP in 51 Chen, this issue;Lin, this issue. 52 Rigger 2011, 4-5. 53  China and the Democratic Progressive Party (DPP) and KMT in Taiwan. Myriad factors todaythe lack of consensus within Taiwan regarding relations with the PRC, a consolidating exclusively Taiwanese identity, Xi Jinping's 习近平 call for applying the "one country, two systems" formula to "reunification" with Taiwan, the effective collapse of the "one country, two systems" model in Hong Kong since 2020, and the DPP's electoral victories in 2016 and 2020have collectively placed the "one China" framework under unprecedented strain across the Taiwan Strait. Under these new circumstances, finding and maintaining a modus vivendi within the framework that is tolerable to Taiwan's democratic electorate and acceptable to Beijing is challenging political leaders' imagination. And it presents arguably the most fundamental test of the informal institution's flexibility since its effective international consolidation 50 years ago. 55

Frictions beyond the international political realm
Another increasingly prominent feature of the PRC's campaign to boldly assert its "one-China principle" goes beyond the Strait as Beijing proactively polices even overseas non-governmental entities' language concerning Taiwan. For many democratic governments, Beijing is perceived to be exploiting its selfdefined "principle" to undermine freedom of speech overseas. 56 Recent years have witnessed numerous instances of foreign businesses, non-governmental organizations, Hollywood and sports celebrities, and even local governments or other institutions being pressured to treat Taiwan as part of China. For example, in 2018, Beijing famously shut down the Marriott hotel chain's website after its customer survey listed Taiwan as a separate country, forcing Marriott to apologize. In 2021, the PRC even demanded that a high school in Colorado "correct" a reference to Taiwan on its school website as a condition for attending the UN Commission on the Status of Women. 57 This trend has introduced new drivers of international and even domestic political friction in foreign countries over "one China" and invited backlash from their governments. For example, in response to Beijing's demand that major US airline carriers change how Taiwan was referenced on their websites, the US government issued a statement demanding that Beijing "stop threatening and coercing American carriers and citizens" and expressing concern about "a growing trend by the Chinese Communist Party to impose its political views on American citizens and private companies." 58 55 Chen, this issue. 56 We are grateful to an anonymous reviewer for encouraging us to highlight this point. 57 Stu Woo, "China makes sure everyone writes Taiwan's name just soeven a Colorado high school," Wall Street Journal, 10 September 2021, https://www.wsj.com/articles/china-makes-sure-everyonewrites-taiwans-name-just-soeven-a-colorado-high-school-11631304386. 58 "Statement on China's political correctness," American Presidency Project, 5 May 2018, https://www. presidency.ucsb.edu/documents/statement-the-press-secretary-chinas-political-correctness.

Trouble ahead? An ambiguous framework confronts unprecedented strain
The Cold War's end eliminated the shared Soviet threat that initially made the ambiguities embodied in the "one China" framework tolerable and geopolitically expedient. Today, however, as the US, Japan and other major democracies' concerns about Beijing's expanding power, international behaviour, and crackdowns in Xinjiang and Hong Kong grow, interest in bolstering practical cooperation with democratic Taiwan as a partner appears to be deepening. So too has an apparent willingness to publicly push back against Beijing's efforts to shrink Taiwan's international spacefor example, Beijing's post-2017 denial of Taiwan's observer status at the WHO, even amid a global pandemic.
Remarkably, this international pushback and support for Taiwan is not limited to major powers. 59 Even the EU and several small European nations appear eager to deepen ties with Taiwan. 60 Most remarkably, the small Baltic nation of Lithuania demonstrated solidarity with Taipei despite Beijing's threats, downgrading of diplomatic ties, and economic coercion. 61 Furthermore, an unprecedented cascade in 2021 of bilateral and multilateral statements issued by US democratic allies "underscor[ing] the importance of peace and stability across the Taiwan Strait," "encourag[ing] the peaceful resolution of cross-Strait issues" and/or calling for Taiwan's "meaningful participation in international organizations," inter alia, demonstrate that geopolitical and geo-economic concerns vis-à-vis China have diminished major democracies' strategic interest in accommodating Beijing's hard line on "one China." 62 Of potentially greatest significance, in response to perceived sabre-rattling from Beijing, US President Joe Biden has even suggested a US commitment to Taiwan's defence that some interpret as indicating a departure from the US's long-standing posture known as "strategic ambiguity." In response, Beijing demanded that Washington "scrupulously abide by the one-China principle." 63 Concurrently, China's growing power and influence and a weakening perception of common strategic purpose with the US and other players appear to have reduced Beijing's tolerance of the "one China" framework's inherent ambiguities. Internationally, Beijing has become more assertive in demanding that all states, international organizations, and increasingly non-state actors as well, embrace Beijing's self-asserted position on "one China." Across the Strait, China's hardening position manifests in its post-2016 refusal to engage in quasi-official dialogue with Taipei, increasingly frequent and provocative military exercises near Taiwan, and freezing Taipei out of international organizations (such as the WHO) with which it was previously allowed to engage. 59 Kastner et al.,  China's growing willingness to use military, diplomatic, economic and other means to pressure Taiwan and third parties to toe Beijing's line on "one China" has threatened to shrink the international space crucial for Taiwan's economic vitality and democratic vibrancy, further undermining Taipei's interests in staying within the "one China" framework. Deepening perceptions in key foreign democratic capitals that Beijing poses a growing threat to Taiwan's consolidated democracy and effective autonomy have led them to voice interest in deepening cooperation with Taipei. From Beijing's perspective, increased international support for Taiwan has further consolidated a long-extant belief that the US and others seek to contain China's rise and "national rejuvenation." The net result is worsening geopolitical and geo-economic frictions and questions about the continuing viability of the "one China" framework.
Thus, 50 years after 1972, the "one China" framework's purpose-built ambiguities face unprecedented challenges, and it remains to be seen how far its vague and amorphous bounds can be stretched. Today, Beijing asserts its sovereignty claim over Taiwan and manoeuvres to shrink its international space with increasing boldness, Taipei tries to parry Beijing's pressure and preserve its democracy and effective autonomy by diversifying its international connections, and Washington, Tokyo and other democratic partners try to support Taiwan's resilience and peace and stability across the Straitall while avoiding Beijing's "red line." Potentially at risk are the implicit assurances provided by the framework's long-standing ambiguities: for China, the idea that peaceful "unification" is possible; for democratic Taiwan, that any future settlement will not violate its citizens' free will; and for the US, Japan and many other democracies, that substantiveif unofficialties and practical cooperation with Taiwan can sustain and deepen without inviting a confrontation with Beijing.

Conclusion
This lead article has explored the consolidation and practical consequences of the "one China" framework since the early 1970s as an informal institution of international politicsone which has fundamentally enabled and politically conditioned China's engagement with the US, Japan, much of Europe and other major powers ever since. The flexibility and vagueness built into the framework in the 1970s made possible China's cooperation with the US, Japan and other key democracies during the late Cold War, significantly facilitating China's subsequent "rise." Fifty years after Nixon's groundbreaking visit and the normalization of Japan-PRC relations, however, real-world developments raise serious questions about the framework's continued viability and, by extension, the sustainability of peace and stability across the Taiwan Strait. China's growing power and intolerance for perceived departures from its self-asserted "one-China principle"; Taiwan's robust democratization, together with the US's and other major democracies' deepening practical support for Taiwan's effective autonomy in the face of mounting pressure from Beijing; and China's increasingly fraught relations with Washington and most major US democratic allies more generally conspire to present the ambiguities that have made the "one China" framework so successful over the past half-century with perhaps its greatest challenge to date.
As an indication of complexity today, although Beijing's renewed effort since 2016 to isolate Taiwan internationally has reduced Taipei's official diplomatic partners from 21 to 14, the substantively meaningfulif "unofficial"ties and support Taiwan receives from the US, Japan, the EU and other major democracies have never been greater. Yet none of the latter actually recognize Taiwan as a sovereign state.
Against this ever more complicated backdrop, it is important for scholars, journalists and policymakers to appreciate not only the contemporary and variable manifestations of the "one China" framework in international politics but also the decades-old modus vivendi that made them possible. Contrary to what Beijing asserts, there is no "international consensus" concerning its "one-China principle." As the late Alan Romberg advised, for the framework to continue to work, it would "require…not just finesse and sensitivity, but a clear understanding about the nature of the ambiguity, the issue it left unresolved, the commitments that permit it to function, and the red lines that could cause it to collapse." 64 As policymakers consider future steps, it is worth reflecting on what then former US policymakers (now both serving in the Biden administration) have called "the greatest unclaimed success in the history of US-Chinese relations"one with the potential to serve as a model for constructive engagement with the PRC "on a variety of other issues, which are similarly likely to include intense engagement, mutual vigilance and a degree of distrust, and a measure of patience and necessary restraint." 65