Role Theory, Foreign Policy, and the Social Construction of Sovereignty: Brexit Stage Right

The international roles states play in world politics are bound up with the ways in which sovereignty is constructed within the international system. While scholarship on sovereignty has recognized its social construction, and role research emphasizes social interactions as shaping roles and role behaviors, little work has explored the relationship between sovereignty and roles. Linking roles and sovereignty offers a distinct perspective on the social construction of sovereignty, providing a broad conception of socialization, emphasizing agency, and bridging domestic politics and international relations. We develop the concept of a “sovereignty–role nexus” through an examination of Brexit, revealing, through processes of role contestation and role socialization, multiple and competing constructions of the nature and value of sovereignty. While Brexit is unique, we suggest that these dynamics will affect other cases where states face role changes linked to sovereignty concerns.


Introduction
The UK's exit from the European Union (Brexit) signals a seismic shift in its foreign policy orientation toward Europe and its roles as a regional and global actor. Although the full scope of change in the UK's foreign policy and its relationship with Europe is not yet known, the Brexit referendum and withdrawal negotiations nevertheless initiated a significant effort to abandon the UK's role as an EU member. For the UK, this role change involved deep concerns about the nature and meaning of sovereignty, which can be conceived as prevailing "norms of sovereignty." These norms, we argue, are foundational to states' foreign policy roles. Norms of sovereignty define what kinds of actors can hold a sovereign role, what sorts of roles are available and legitimate to pursue, and what sovereign powers they have for performing other, substantive roles such as "great power," "faithful ally," or "neutral." Because enacting roles involves both domestic contestation and international socialization around appropriate state behaviors, role-seeking is a social process that can influence how sovereignty is constructed. Constructivist research on sovereignty norms has examined the social nature of sovereignty, and role theorists have explored the social construction of roles, yet there has been little attention to the interplay between sovereignty norms and foreign policy roles. We address this gap by examining domestic and international sovereignty-role dynamics revealed in Brexit.
We begin with a discussion of a role theory view of sovereignty norms, noting key differences from constructivist research on sovereignty before outlining four ways norms of sovereignty and roles are connected. We argue that role theory furthers our understanding of how sovereignty in the international system can be constructed, both shaping and being shaped by foreign policy roles and the broader international role system. This highlights key difficulties the UK has experienced in repositioning itself into an international role that simultaneously meets its various domestic desires for greater control, its international foreign policy ambitions, is acceptable to international actors, and comports with prevailing sovereignty norms around anti-colonialism and the liberal international order. Like many major international turning points involving multiple causes, contingencies, and conjunctions of events (Lebow 2000), the Brexit referendum may have been an unpredictable catalyst, but the subsequent processes it launched give us an opportunity to contribute to role change research by focusing on sovereignty dynamics. Scholars have identified different types of role change such as adaptation, learning, and identity transformation (Harnisch, Frank, and Maull 2011b), the processes involved (Thies 2013;Wehner and Thies 2014;Beneš and Harnisch 2015), and investigated different change and stability dynamics in various cases (e.g., Klose 2020;McCourt 2020;Teles Faszendeiro 2020;Wehner 2020), including the UK (e.g., Gaskarth 2014;McCourt 2014). Our approach contributes to these efforts by focusing on role changes stemming from sovereignty concerns. By connecting both contestation and socialization to sovereignty norms, we are able to demonstrate how efforts to change roles can reverberate, affecting multiple states as well as the international system more broadly. We argue this generates some existential resistance to role changes, since they have the potential to affect the larger normative context around sovereignty upon which roles are built, prompting reactions from a wide range of actors who themselves have little material stake in an actor's role change. Finally, role theory gives us a distinct agent-based perspective on the construction of international norms, while also suggesting how norms of sovereignty can constrain role changes, particularly those prompted by sovereignty as a central concern.

The Sovereignty-Role Nexus
First introduced to the study of international relations some fifty years ago by Holsti (1970), role theory bridges levels of analysis, structures and agents, and material, ideational, and normative factors, providing a conceptually rich theoretical framework for understanding complex social processes (Harnisch, Frank, and Maull 2011a;Thies and Breuning 2012). Role theory is sociological, drawing on the metaphor of the theatre, with actors in a society playing roles, such as "great power" and "bridge" (Holsti 1970). Rooted in symbolic interactionism, roles are not static but instead are constructed through interactions between the actor (Ego) and others (Alters). Actors may have their own conceptions of roles they wish to play, but as roles are relational, they must be socially negotiated. This involves Ego enacting a role and Alters responding through altercasting, resulting in a socialization process whereby Ego may adopt a mutually acceptable role. A role theory approach differs from realist approaches that focus instead on whether states have the objective capabilities to play certain roles (Blagden 2019).
For role theory, the "sovereign state" is itself a role that comes with specific expectations for Ego and from Alters (Barnett 1993;Thies 2013;Beasley and Kaarbo 2018). For Ego to play a sovereign role, Alters must recognize it as a legitimate actor to hold a sovereign role, and accept the sovereign role as granting Ego an agreed set of sovereign powers for enacting other roles. We see these as norms of sovereignty-ideas that establish and set parameters for the nature of agency and scope of acceptable behaviors for the sovereign role within the international system. As Philpott argued, sovereignty norms establish what kind of "polity" is capable of holding sovereignty (e.g., empires, states), which actors can become sovereign (e.g., former colonies, the EU), and what powers sovereignty provides (e.g., signing trade agreements, regulating immigration) (Philpott 1995(Philpott , 2001. International society, through sovereignty norms, de-fines agency for holding roles and constructs the legitimate behaviors such actors can perform when enacting substantive roles (e.g., "great power," "neutral"). Different historical eras have entailed different sovereignty norms (Philpott 1995(Philpott , 2001 with different notions of agency for role holding and enactment, thereby affecting the types of roles that are possible within the international system. In these ways, roles can be viewed as "constructed repositories of sovereignty within international society" (Beasley and Kaarbo 2018, 9); playing the sovereign role is the behavioral expression of the normative ideas of what sovereignty means.
There are numerous approaches to sovereignty (for reviews, see Jackson 1990;Lake 2003;MacFarlane and Sabanadze 2013), including constructivist accounts (see Onuf 1991;Wendt 1992;Biersteker and Weber 1996). Such accounts have challenged the functionalist view that sovereignty is an achieved status and the realist view that sovereignty is an objective characteristic of actors that has a single meaning. Instead, constructivist approaches to sovereignty argue that like anarchy, sovereignty is socially constructed. While sovereignty can be generally understood as an actor's "externally recognized right to exercise final authority over its affairs" (Biersteker and Weber 1996, 2), 1 actors embedded in social systems have varying understandings of what sovereignty means and how it is practiced. Norms of sovereignty are a prominent feature of its social construction and have been studied fairly extensively, focusing on military basing (Schmidt 2014), military interventions (Ramos 2013), and regional (Coe 2015) and temporal variations (MacFarlane and Sabanadze 2013).
A role theory approach to sovereignty, however, emphasizes both agency and behavior differently than approaches focusing only on sovereignty norms, shedding new light on dynamics involved in the construction of sovereignty. First, role theory, with its roots in foreign policy analysis, emphasizes and interrogates the agency of states and other political actors. States' roles stem from a variety of agentbased sources, such as material and ideological properties that shape states' conceptions of their national roles. Since states have agency in choosing and constructing their roles, norms of sovereignty may be selected and even modified in pursuit of a particular role. Role theory also unpacks agents' domestic politics more explicitly than work on the domestic politics of norms (e.g., Acharya 2004;Wiener 2007;Bloomfield and Scott 2016;Risse 2016). Role theory does not assume a single state identity or national role conception, instead allowing for vertical and horizontal role contestation across various sites that potentially affect roleplaying and role change (Wehner and Thies 2014;Cantir and Kaarbo 2016a). Since roles can be contested domestically, sovereignty norms can also become part of domestic debates about which roles should be pursued (inter-role conflict) and the meaning of the sovereign role (intra-role conflict) (for more on inter-and intra-role conflict, see Harnisch, Frank, and Maull 2011b;Hansel and Möller 2015). In this way, sovereignty not only is constructed and has multiple meanings, but is contested as well. This contestation at multiple levels of agency also means that norms may not be internalized, as much of the constructivist work on socialization assumes (Thies 2013). With this attention to state agency, role theory bridges agents and normative structures as roles are "an important link between agent and structure" (Barnett 1993, 272; see also Thies and Breuning 1 While we offer this as an illustrative definition, our empirical approach examines discourses around sovereignty and the meaning that actors discursively attach to sovereignty. 2012). This bridge is consistent with research emphasizing domestic sources of foreign policy, and is especially relevant to sovereignty construction, given sovereignty's internal (ultimate authority within a state's territory) and external (recognition of that authority) dimensions (Lake 2003).
Second, role theory offers a distinct and novel perspective on the construction of sovereignty with its behavioral focus. As properties of agents rather than normative structures, roles are more directly connected to actors' behaviors. Role theory sees norms as only one element of roles, facilitating but not determining role behavior. As Biddle (1986, 71) notes: "norms are said to provide merely a set of broad imperatives within which the details of roles can be worked out. Actual roles, then, are thought to reflect norms, attitudes, contextual demands, negotiation, and the evolving definition of the situation as understood by the actors." Multiple norms of sovereignty could be incorporated into a single role to help define expected behaviors, and roles may also guide actors' behaviors when norms of sovereignty are contested, indeterminate, or uncertain in a given situation. Norms of sovereignty may be part of a broader suite of factors affecting the enactment of roles, since role behavior may come not only from international normative expectations, but also from role demands of the situation and from other actors' specific behavioral role expectations (Walker 1992;Aggestam 2006). From a role theory perspective, socialization is broadly defined, going beyond socializing agents to norms and including socialization of role behaviors (Thies 2013).
These differences effectively position role theory for understanding the social construction of sovereignty when states face sovereignty concerns. Since sovereignty norms are a constitutive element of roles, they are an especially significant feature of role change driven by sovereignty concerns. In turn, role contestation and socialization processes can engage with and potentially alter different norms of sovereignty as a state attempts to change its role within the international system. Role theory has already been connected to the sovereign role (Barnett 1993;Thies 2012), most directly through the concept of the sovereignty-role nexus (Beasley and Kaarbo 2018). Through role behaviors by Ego and Alter(s), we can see the nexus between sovereignty and roles in four different dynamics: (1) debates over the value and meaning of the sovereign role, (2) linking of sovereignty to specific substantive foreign policy roles for both Ego and (3) Alters, and (4) challenges to prevailing sovereignty norms within the international system. We explain these dynamics and examine each of them in the Brexit case.
The Brexit case-which for our purposes extends from the Brexit referendum in June 2016 until the UK and EU agreed a draft withdrawal agreement in October 2019offers particular advantages for developing the sovereigntyrole nexus. Brexit represents a significant role change for the UK and thus activated both contestation and socialization. Because Brexit debates turned in good measure on "regaining sovereignty" domestically and also involved the complicated process of extricating Britain from EU treaties, it allows us to effectively illustrate our theoretical development of the sovereignty-role nexus at both domestic and international levels. We do believe these dynamics are also evident and important in other types of role changes, as we discuss in our conclusions. We organize the case presentation along the four dimensions of the sovereignty-role nexus to better illustrate the different dynamics they involve.
Our empirical demonstration of these four dimensions primarily consists of verbal statements and claims of high-level decision-makers in the UK and internationally. In the UK, we include views of the "Leave" and "Remain" sides during the referendum, post-referendum government discourse and parliamentary debates, and voices from the devolved administrations in Scotland and Northern Ireland. On the international level, our analysis mainly invokes statements of states' and international organizations' representatives who commented on post-Brexit UK role changes. Our strong reliance on verbal evidence reflects that early indications of the sovereignty-role nexus in the Brexit case were mostly discursive. To the extent possible, we complement our analysis with behavioral evidence, including votes in parliament and court rulings in the UK as well international behaviors of the UK and other international actors, for example, at the UN.
This empirical strategy follows well-established practice in role theory research, which often uses speech acts and other actions of high-level actors to substantiate its argument (Breuning 2018). We do not, however, claim that these are causally driving the role transformation and reactions to it. 2 Nor do we assume that speech acts necessarily reflect genuine views. Consistent with role theory, our analysis shows discourses and behaviors constructing understandings of role conceptions and expectations (Walker 1992;Breuning 2011;Wehner and Thies 2014). We use the Brexit case to demonstrate that contestation and socialization over roles are underlying processes in the social construction of sovereignty and involve prevailing and contested sovereignty norms.

The Sovereignty-Role Nexus in Brexit
The decision to hold the Brexit referendum stemmed from internal contestation over the UK's European role within the Conservative Party and rising support for the UK Independence Party (UKIP) (Clarke, Goodwin, and Whiteley 2017). During and after the referendum, domestic debate focused on issues connected to sovereignty and its relative value for Britain (Hobolt 2016;Auer 2017). "Leavers," led by right-leaning parties and populist sentiments, pushed for a British exit from the European stage (a "Brexit stage right"), emphasizing the desire for Britain to "take back control" from EU institutions. The Leave side was primarily represented by UKIP and key Conservative Party figures, although the Conservatives were divided over Brexit. The Remain side was led by PM David Cameron and supported by most representatives of the other political parties (for a detailed discussion of the Leave and Remain sides, see Clarke, Goodwin, and Whiteley 2017). Contestation continued through the 2017 national election where PM Theresa May's Conservatives lost their parliamentary majority, with an electoral "backlash against the vote for Brexit and direction of the Brexit process" (Heath and Goodwin 2017, 350). After that, ongoing contestation over Brexit in intra-party, intra-cabinet, parliamentary, and legal arenas saw PM May being replaced by Boris Johnson and was critical in triggering another general election in December 2019. This election returned an absolute Conservative majority, leading to the passing of a Brexit withdrawal agreement in January 2020. 2 Our purpose is not to explain Brexit but instead to develop our theoretical argument. Explanations of Brexit have focused, inter alia, on domestic political drivers (e.g., Hobolt 2016), historical, sociological, normative, and legal contexts (e.g., Gordon 2016; Wiener 2017), identity and performativity (e.g., Adler-Nissen, Galpin, and Rosamond 2017), economic and cultural consequences of globalization (Blagden 2017), and security relations at the international level (e.g., Rees 2017).
External actors also weighed in on the possible roles the UK could play post-Brexit with socialization efforts overwhelmingly supporting the Remain side (Oliver 2016a). Spokespersons for EU institutions, international organizations, and many foreign governments made explicit statements against Brexit, arguing that the UK would be weaker outside the EU, that negotiations about the UK's post-Brexit relationships would not be straightforward, and that Brexit would have negative economic consequences. Exceptions were Donald Trump, first as presidential candidate and then as US president, who embraced Brexit (Trump 2017a) and Russia, which reportedly supported Brexit to capitalize on weakness it might bring to Britain (Colson 2018). We next demonstrate how socialization and contestation in the UK's role change activated different and contested constructions of sovereignty, which can be seen through the four dynamics of the sovereignty-role nexus.

The Value, Meaning, and Location of Sovereignty
The first dynamic of the sovereignty-role nexus involves debates about sovereignty and the sovereign role itself. If sovereignty is a significant concern, there will be pressure to clarify how sovereignty has been affected and how it relates to any potential role changes Ego seeks. Debates about changing the sovereign role may involve the degree of autonomy sovereignty provides from outside interference, the specific powers it entails for changing significant policies, and where it is thought to reside domestically. Questions of the value and purpose of sovereignty may also surface in role socialization, as external actors advance substantive claims about what playing the sovereign role implies.
Both contestation and socialization over having a "more sovereign role" exposed different understandings of sovereignty in the Brexit case (Auer 2017), as revealed in public discourses. Although the UK is a sovereign state, the Leave campaign argued that its sovereignty was constrained and that outside the EU it would enjoy more sovereignty, more independence, thus characterizing sovereignty as continuous, not dichotomous. The Conservative Party has long been divided over the UK's relationship with the EU around issues pertaining to UK sovereignty (Wallace 1986;Oliver 2015). Sovereignty was also an overarching theme for the Leave side, with its "take back control" slogan and its claim that Brexit meant regaining control over the economy, security, and borders. One Leave poster put it bluntly: "Brexit: A Chance to Bring Back Sovereignty," and another poster claimed: "We Want Our Country Back." For prominent Leave campaigner and subsequently Foreign Minister and PM Johnson, a referendum vote to leave would be Britain's "independence day" (Independent 2016a).
Contestation revolved around specific policy issues directly connected to the UK's sovereign powers, particularly immigration and the economy (Auer 2017). The Leave campaign built much of its case for Brexit on an antiimmigration platform, arguing that the free movement of people required with EU membership compromised the UK's ability to control its sovereign borders (Cummings 2017). Economically, Leavers focused on money flows to Brussels and on lost economic opportunities of more free trade with non-EU states, while Remainers touted the net economic benefits to EU membership, including being part of a larger trading actor (Clarke, Goodwin, and Whiteley 2017). Groups across the political spectrum supported Brexit, including "hyper-globalists," anti-globalization groups, critics of the EU's "democratic deficit," and nationalists/isolationists (so-called little Eng-landers) (Adler-Nissen, Galpin, and Rosamond 2017; Blagden 2017).
Although foreign policy did not figure very prominently in the referendum, the two camps still articulated distinguishable views on the UK's role in the international system (Martill and Rogstad 2019). While the Leave side emphasized the powers (especially around immigration and the economy) that sovereignty should provide, the Remain side's arguments emphasized what types of actors can be sovereign. In an interdependent world, argued Remainers, country-based notions of sovereignty are old-fashioned, and the EU's pooled sovereignty is a more modern conception of power and authority. As PM Cameron argued, sovereignty does not necessarily mean influence, and sovereignty after Brexit would only provide an "illusion of power" (quoted in Parker 2016). Implicit in these arguments is the belief that sovereignty is less valued for smaller units, given interdependence. Indeed, one key theme for the Remain campaign was that EU membership amplifies the UK's capabilities and its potential to have influence in the world (Cameron 2016a). Remainers argued that pooled sovereignty is not necessarily a restriction of sovereignty; consensual decision-making for EU external actions means that the UK does not have to act against its own preferences (Burnham 2016).
International responses to Brexit reflected the Remain side's view of sovereignty, with many actors asserting that the EU membership role enhanced the UK's weight as an international partner. New Zealand PM Key, for example, said: "We certainly think it is a stronger position for Britain to be in Europe" (NZ Herald 2016). German Finance Minister Schäuble suggested that, given high interdependence between European economies, leaving the EU would weaken the UK's ability to play a sovereign role: "In the era of globalisation, 'splendid isolation' is not a smart option" (Spiegel 2016). Similarly, MPs of the German Bundestag (in interviews, June 2017) strongly believed Brexit was an act of selfdemotion of the UK in international arenas and that the UK would not even be able to play a middle power role. 3 This mirrors the Remain side's conception of individual state sovereignty as limited in an interdependent world. One EU Brexit official even suggested "there is no such thing as a sovereign country anymore … it is an illusion the Brits are all chasing" (Barker 2018). President Obama (2016) stated explicitly that EU membership "magnifies the power of the UK. It doesn't diminish it." Leave's reaction, however, was focused on sovereignty as domestic control, with Boris Johnson labeling as hypocritical US suggestions that "we must surrender control of so much of our democracy" (Johnson 2016a).
The only significant international support for the Leave side came from Trump and Russia. While Putin's position may have been simply to gain power against a weakened UK (Colson 2018), Trump's position resonated with his "America First" agenda emphasizing the "founding principle of sovereignty" (Trump 2017b) in foreign affairs. He suggested Britain would be "better off without" the EU precisely because EU membership restricts Britain's sovereignty on issues such as migration (Reuters 2016a). Trump also praised the "free and independent Britain" that emerged from its decision to leave the EU (Trump 2017a). The US political right more broadly saw Brexit as allowing the UK to act more freely on the international stage and to offer more leadership in transatlantic relations (Rees 2017). This stands in contrast to the views of US President Joe Biden who previously spoke out against Brexit as Vice President in the Obama administration, warning against "reactionary politicians and demagogues peddling xenophobia, nationalism, and isolationism" (Politico 2016).
Brexit also became entangled with the question of internal sovereignty (Oliver 2015;Wiener 2017)-who in the UK had the right to make this role change? Legal processes for implementing Brexit became part of domestic role contestation with arguments about where sovereignty lies: in the "will of the people," in parliament, in devolved political authorities, or in the central UK government. The May-led government argued it alone had the executive privilege to trigger Article 50 of the Treaty of Lisbon, which sets the EU exit process in motion, but the Supreme Court ruled that Parliament had to be consulted, thereby limiting Executive power (Guardian 2017a) and transferring the contestation process to Parliament.
Sovereignty was a significant issue throughout the Brexit parliamentary debates (Gordon 2016). While the House of Commons voted overwhelmingly to back the government's European Union Bill, to trigger Article 50, many MPs did so out of respect and deference to popular sovereignty, as expressed in the Brexit referendum. Contestation between parliament and the government over sovereign control for enacting role change continued into 2017, as parliament delivered PM May a significant defeat by declaring its right to have a "meaningful" vote on the final Brexit deal (Guardian 2017b). PM May rejected calls across the political spectrum to delegate control over Brexit back to the people in a second referendum , even in the face of repeated government defeats on its Brexit deal (Reuters 2019). While PM Johnson secured a narrow parliamentary majority for a renegotiated withdrawal agreement in October 2019, parliament subsequently voted down the government timetable for implementing the agreement, leading the government to pause legislation (BBC News 2019a). The deadlock between parliament and government was only resolved through a general election in December 2019, which strengthened the hand of the Johnson-led government and finally enabled it to push its Brexit bill through the House of Commons (BBC News 2020).
Sovereignty's location was also contested across the UK's devolved political system (Keating 2019), as the four constituent territories voted differently in the referendum (with majorities in England and Wales favoring Brexit and majorities in Scotland and Northern Ireland opposed). Scottish First Minister Sturgeon argued that Brexit should require majority support in each UK territory (McHarg and Mitchell 2017). The UK government decidedly rejected this or any opt-out or veto from Scotland (Telegraph 2016a). In the 2017 UK Supreme Court Brexit case, "the various devolution submissions presented a … radical and pluralist vision of the location of constitutional authority within the United Kingdom" (McHarg and Mitchell 2017, 521). The Court ruled in favor of the central government but declined to rule definitively on the status of the devolved units in the actual withdrawal from EU laws. The Scottish government continued to argue that each territory should have more involvement in Brexit negotiations (The National 2018). As for Northern Ireland, the small Democratic Unionist Party led opposition to the "backstop" proposed in the EU-UK withdrawal agreement, which it criticized as a threat to the sovereign integrity of the UK, and used its pivotal position in parliament, between the 2017 and 2019 general elections, to thwart government attempts to secure a majority for the agreement (Hayward and Vaughan 2019).
Seeking a more sovereign role revealed differing conceptions of the nature and location of sovereignty, with some emphasizing domestic policy powers and the will of the people, and others attempting to wrest control out of Whitehall and into parliament or the devolved authorities. Some in the international community focused on the advantages afforded by pooling sovereignty through the EU. In this way, Brexit represented a role change that generated intense discursive and-to a lesser extent-behavioral contestation involving the nature of sovereignty, which in turn became connected to more specific foreign policy roles that sovereignty might afford.

Casting and Socializing Foreign Policy Roles
The second dynamic of the sovereignty-role nexus involves new substantive roles sought and available for Ego. What potential foreign policy roles become accessible if more sovereignty is acquired, and how well would they address sovereignty concerns? Here, contestation involves domestic actors putting forward different national role conceptions about substantive foreign policy roles (e.g., neutral state, global leader). Because sovereignty in this way becomes part of the role location process, it is also a significant factor in role socialization. As Ego explores new roles that might address its sovereignty concerns, Alters will highlight sovereignty issues for those roles. As with all role socialization, Alters may accept, reject, or shape Ego's roles in accordance with Alters' preferences (Thies 2013). If Alters reject or seek to shape Ego's roles, this may involve role conflict (Cantir and Kaarbo 2016b, 5) between Ego conceptions and Alter expectations around what roles any post-Brexit sovereignty gains allow the UK to play.
Leavers argued more sovereignty would give the UK greater independence to play other substantive foreign policy roles. The UK government casted about for several roles post-Brexit, including global trading state, great power, leader of the Commonwealth, and faithful ally to the United States. Each of these roles offers the UK different opportunities to exercise its post-Brexit sovereignty status and each emphasized somewhat different aspects of sovereignty. These were met by resistance from external actors challenging the notion that sovereignty permits their unilateral pursuit and involved inter-role conflict as not all roles cast for were compatible with each other (Oppermann, Beasley, and Kaarbo 2020).
The UK government projected two global roles-global trading state and great power-and supported both with rhetoric emphasizing sovereignty as affording great autonomy internationally. Brexit would free the UK from the shackles of the EU and unleash the UK's potential as a global actor (Daddow 2019). PM May (2017a) argued that the UK is "by instinct a great, global, trading nation." After Brexit, it will remain a "champion for free trade right across the globe" (May 2018a) and become a "truly Global Britain" (May 2017a). For the great power role, the UK government emphasized its "global reach and world class capability" (Williamson 2018), including its economic strength (Johnson 2017), "unrivalled" soft power (May 2018b), and its status as a permanent member of the UN Security Council (May 2017b) and "a leading member of NATO" (May 2017c). PM May highlighted the UK's great power capabilities, arguing its new aircraft carriers "will transform the UK's ability to project power around the world" (May 2017c). Government decisions to reinforce UK contributions to NATO forces "on the ground" (Telegraph 2016b) and to achieve an "enduring presence" of the Royal Navy in the Persian Gulf serve as behavioral evidence that underlines UK ambitions to great power status (Williamson 2018). Similarly, the UK re-opening of a naval support facility in Bahrain was, according to FM Johnson, a signal that "Britain is back East of Suez" (Johnson 2016b), reversing Britain's Cold War military disengagement from that part of the world, which symbolized its retreat from a great power role (Self 2010). Those arguing for these global roles characterized greater sovereignty as greater power and autonomy, extending the UK's reach and global importance. Indeed, PM May argued the referendum was "a vote to take control and make decisions for ourselves and, crucially, to become even more global and internationalist" (May 2017a), and "to reassert our belief in a confident, sovereign and global Britain" (May 2017d).
These global roles met rhetorical and behavioral resistance from many international actors who see "regaining sovereignty" as an isolating and diminishing act that would reveal the UK as a middle power for whom global roles are unavailable (Oliver 2016b; Wilson and Oliver 2019). For some, Brexit accelerates a longer term decline in the UK's influence that has it moving from the "first team" to the "reserve bench" in international politics (Niblett 2015, 10). President of the European Commission Juncker warned that the "UK will have to get used to being regarded as a thirdparty state" (Financial Times 2016a). US President Obama (2016) cautioned that the "UK is going to be in the back of the queue" for trade deals. Indeed, major non-EU trading partners of the UK have largely rebuffed British overtures to secure bilateral trade commitments, at best offering to copy and paste their trading relations with the EU. For example, Japanese officials made clear that they prioritize free trade negotiations with the EU over the UK (Guardian 2017c), and a 2018 visit of FM Hunt to Beijing did not achieve tangible results on the UK's post-Brexit trading relationship with China (Hunt 2018). Moreover, Brexit was widely expected to weaken the influence Britain exercises in the UN (Dee and Smith 2017). Behaviorally, this expectation can be seen in the UK's failure to win support in the UN General Assembly for its candidate as judge in the International Court of Justice (ICJ), leaving it without a judge for the first time in the court's history, which was described as "a humiliating blow to British international prestige" (Guardian 2017d). Far from enhancing its global roles, any gains in sovereignty Brexit affords would unravel its global ties and reveal a weak and isolated UK.
The UK has, however, actively tried to avoid the role of isolate (Oliver 2016b). Since Leavers promised that Brexit will enable the UK to play new and enhanced foreign policy roles after Brexit, this is central to the UK government's domestic and international credibility (see Teles Faszendeiro 2020). Given that the isolate role contradicts ingrained public and elite beliefs about the UK's place in the world (Gaskarth 2014, 566-69), resistance to being cast into this role post-Brexit may also involve efforts at maintaining a stable identity (see Klose 2020). Thus, Boris Johnson (quoted in Independent 2016b) drew "a very, very strong contrast between Brexit and any kind of isolationism" and PM May (2018b) emphasized that Brexit "was not a rejection of multilateralism or international cooperation." For Trade Secretary Liam Fox (2017), Brexit did not mean "the United Kingdom would be withdrawing from the world stage." Similarly, PM May (2017b) proclaimed: "We may be leaving the European Union but we are not leaving Europe" and that relations with Europe can be better pursued from the position of "a sovereign nation in which the British people are in control." Yet, the widespread view among international observers was that Brexit meant a "voyage to inglorious isolation" (New York Times 2017) and an "isolationist catastrophe" (Los Angeles Times 2016).
The UK's casting for leader of the Commonwealth role also met with skepticism. The government foregrounded the UK's position as "a driving force in the Commonwealth"  with official visits to Commonwealth countries highlighting "common values among its members" (Johnson 2017), and prioritizing trade relations (May 2017a). The Commonwealth role speaks to domestic constituencies nostalgic for Britain's imperial past (Turner 2019) but Commonwealth countries have not supported this role, preferring a UK in the EU, or the EU, over a Brexited UK (Guardian 2016a; Namusoke 2016). The Secretary-General of the Commonwealth rejected as a "false choice" suggestions that the UK's Commonwealth links should replace its EU membership (Reuters 2016b). Moreover, the role was criticized for its neocolonial connotations (Guardian 2016a; Adler-Nissen, Galpin, and Rosamond 2017) and was branded, by skeptical officials inside Whitehall, as "Empire 2.0" (Civil Service World 2017). While the leader of the Commonwealth role resonates with many policymakers' understandings of the UK's long-term identity, it clashes with Commonwealth members' own role conceptions along sovereignty lines (see Klose 2020).
Faithful ally to the United States is another potential post-Brexit UK role, but one that could transform sovereignty's independence into greater dependence on the United States (Bew and Elefteriu 2016). The UK affirmed this "special relationship" (Wilson 2017), with PM May (2017d) asserting: "we have the opportunity -indeed the responsibility -to renew the special relationship for this new age." The Trump administration in the United States generally accepted this faithful ally role, at least rhetorically (Guardian 2016b). Given his views on the importance of state sovereignty, President Trump embraced the special relationship, inviting PM May as his first official guest in Washington (Trump 2017a). Nevertheless, the US-UK relationship was tested with trade disputes, Trump's critiques about the UK's response to terrorism and PM May's handling of Brexit, and his comments on intra-party Conservative leadership struggles (BBC News 2018; Sabbagh 2018). The faithful ally role is also contested domestically in the UK, given the high political price the UK pays for sustaining it, not least in terms of-at times unpopular-diplomatic and military support for the United States (Porter 2010).
Overall, early international reactions to Brexit challenge the UK's ability to translate its sovereignty into the substantive roles it seeks, highlighting different constructions of sovereignty in relation to various possible UK roles. While sovereignty may grant the right to negotiate trade deals, project power, or exploit cultural ties, it does not confer trading partners, provide material capabilities, or regain historical status. Domestic visions of sovereignty as greater control crash headlong into international conceptions of a weakened and isolated UK becoming more reliant on its special relationship with the United States and becoming even less special among the Commonwealth.

Implications for Alters' Roles
The third dynamic of the sovereignty-role nexus involves how role change in Ego affects Alter(s)' roles. As roles are relational, any change in Ego's roles can impact Alters' roles, and contestation and socialization may turn on the desirability of those consequences for others. Role Downloaded from https://academic.oup.com/isagsq/article/1/1/ksab001/6153025 by guest on 13 March 2021 changes arising from sovereignty concerns may have distinct sovereignty implications for others. Concerns with such implications in Alters can lead to sovereignty-based role conflicts between Ego and Alter. Alters' socialization efforts towards Ego can also reverberate onto their own roles, prompting domestic contestation about where sovereignty resides and the meaning and construction of sovereignty for Alters' roles. This should be particularly true for Alters who themselves are already facing sovereignty concerns.
Ireland's role vis-à-vis the UK and particularly Northern Ireland may change with Brexit. This change is largely unwanted by the Irish government and is one reason for its opposition to Brexit. A vexing problem in Brexit negotiations was the border between Northern Ireland and the EU member state Republic of Ireland, and the status of Northern Ireland as part of the Republic or part of the UK implicates the UK and Ireland's sovereign boundaries. The Belfast/Good Friday Agreement not only established the way in which Northern Ireland would be governed, but also dealt directly with relations between the Republic of Ireland and the UK. As such, the Brexit border problem has reignited differing sovereignty claims, and various proposed solutions to the movement of people and goods each run into difficulties along these lines (Guardian 2017e;Doyle and Connolly 2019).
The UK government's position was that there can be no return to a "hard border" between the Republic and Northern Ireland, but the EU demanded that the border issue be resolved before other Brexit trade negotiations continued and accused the UK of "magical thinking" with regard to its hope for an "invisible border" (Guardian 2017f). The EU insisted on a "backstop" as a fallback position that would keep Northern Ireland inside the customs union and thus prevent a "hard border" if the UK and the EU failed to reach a comprehensive customs and free trade agreement (Reuters 2018). While the UK government under PM May reluctantly signed up to this idea in principle, it demanded that any "backstop" must only be temporary and UK-wide, arguing that otherwise it "threatens the integrity of our United Kingdom" (May 2018c). PM Johnson, in contrast, negotiated the "backstop" out of the withdrawal agreement, at the cost of a customs border between Northern Ireland and the rest of the UK (Haverty 2019). Because of these sovereignty concerns, Brexit put considerable uncertainty on the Republic of Ireland's role vis-à-vis the EU and the UK and on the sovereign borders of Ireland and the UK.
Given majority support in Scotland for remaining in the EU, the question of a Scottish sovereign role-as was raised through the 2014 independence referendumresurfaced with Brexit. The Scottish government, led by the pro-independence Scottish National Party (SNP), raised the question of another independence referendum immediately following the Brexit referendum (Independent 2017). PMs May and Johnson rejected the call, but another independence referendum remains a possibility, in particular after the strong SNP result in the 2019 national election. Scotland's First Minister Sturgeon's warnings of the "catastrophic prospect" (Guardian 2018) of a no-deal scenario, her demand that Scotland and the whole of the UK remain in the single market, and her objections against any preferential treatment of Northern Ireland all seemed to prepare the ground for another referendum (Politico 2018a). Scottish independence would be another sovereignty-related role transformation resulting from Brexit, affecting the UK's sovereignty and its ability to play other substantive foreign policy roles (Beasley and Kaarbo 2018).
Brexit also has various repercussions for the EU. It impacts power relationships in the EU Council, strengthening the roles of large EU members (most notably Germany, France, and Poland) at the expense of smaller member states (such as Denmark, Ireland, and the Netherlands) who have had close ties to the UK, often pursuing similar policy positions based on shared concerns over EU sovereignty (Huhe, Naurin, and Thomson 2017). In particular, Brexit affects the roles France and Germany play in the EU (Krotz and Schild 2018), pushing them together into a renewed collective EU leadership role.
This can be seen in the EU-UK negotiations on the post-Brexit relationship, in which Franco-German leadership was essential in securing a common EU27 line that prioritized defending the integrity of the EU's internal market (Oppermann, Beasley, and Kaarbo 2020, 141-42). In Germany, Brexit reinvigorated a broad pro-European consensus among mainstream parties, providing it with a new sense of purpose. This enabled the Merkel government to lead in formulating the EU27 response to Brexit (Oppermann 2019, 489-90). Interviewees in the German Bundestag in June 2017 emphasized how Berlin became a key diplomatic hub where positions of EU states were coordinated and how the German government prioritized a close dialogue with its French counterpart. This tied in with French President Macron's view of Brexit as a strategic opportunity to restore Franco-German leadership in the post-Brexit EU (Reuters 2017). To that end, France worked toward a strong Franco-German tandem in the Brexit process, hoping to win German backing for its broader European initiatives, including on European defense (Financial Times 2018). In this way, Brexit, at least initially, revitalized the traditional Franco-German "motor," and thus the roles these states played in the EU, at the heart of the European integration project.
Brexit also has implications for the EU as a global actor. Many worried that an EU minus the UK would be a weaker power economically, militarily, and normatively (see Blockmans and Emerson 2016). This was another reason for international opposition to Brexit as some see the EU as an important liberal, Western force to balance the rise of other actors (Financial Times 2016b). Moreover, some EU member states also face domestic conditions that may involve role contestation and even role change. Although Brexit may rekindle a sense of common purpose among the EU-27 to reinforce pooled sovereignty and undermine arguments by anti-EU parties across Europe (Adler-Nissen, Galpin, and Rosamond 2017), the success of the Leave campaign emboldened some anti-EU movements and political parties in several member states, including France, Greece, the Netherlands, Italy, and the Czech Republic (Hobolt 2016;Pirro, Taggart, and van Kessel 2018). Some fear Brexit will reinforce anti-Europeanism and trigger "a domino effect that may eventually end in the break-up of the EU" (France 24 2016). Consequently, the EU's guiding principle in the Brexit negotiations was that any post-Brexit arrangements must discourage other EU members from following the UK example and thus prevent further erosion of the EU, its role in the world, and its notions of shared sovereignty (Ries et al. 2017).

Broader Implications for the Sovereign System
The fourth dynamic of the sovereignty-role nexus involves challenges to the prevailing norms of sovereignty within the international society of states. Debates involving the value of sovereignty and the types of roles it allows in both Ego and Alter(s) have the potential to challenge or alter important norms of sovereignty, at regional or global levels. Contestation and socialization may involve existential resistance to role change in Ego by Alters if such change is seen to threaten the fabric of international society, and internal and external actors with a stake in the status quo may mobilize to resist role transformation (Armstrong 1993;Jackson 1999), appealing to the importance of established sovereignty norms.
In Brexit, we see these broader implications surface around two significant normative changes in sovereignty: decolonization and the European liberal project. The prosovereignty, right-to-rule-oneself message associated with Brexit has been employed by some to further sovereignty claims and advance anti-colonialist sovereignty norms. Indeed, there have been sovereignty skirmishes prompted by the UK's role transformation, involving lingering unresolved sovereignty questions facing the UK.
The status of Gibraltar was thrown into question when its residents voted overwhelmingly to remain in the EU (McHarg and Mitchell 2017), but nevertheless strongly prefer UK rather than Spanish control of their territory. Spain initially exploited Gibraltar's disputed sovereignty status in the EU negotiating position on Brexit, attempting to give Spain the ability to exclude Gibraltar from future EU-UK trade. A senior UK source noted that "the clause was extraordinary because it effectively signalled a lack of total British sovereignty over Gibraltar" (Guardian 2017g). Subsequently, the Spanish government backed down on Gibraltar, but also signaled, in a change of position, that Spain would not veto Scottish EU membership should Scotland gain independence (Guardian 2017h). In Brexit-related EU legislation regarding UK citizen travel to EU countries, Spain's insertion referred to Gibraltar as "a colony of the British crown," furthering tensions in this 300-year-old dispute (Boffey 2019). Spain also floated ideas of joint sovereignty over Gibraltar. Gibraltar's First Minister, however, rejected this idea, saying "if anyone in Spain … believes we will ever compromise our sovereignty, they are wrong. The concept of joint sovereignty or any dilution of our sovereignty is a dead duck" (Nayler 2019).
Other instances involve sovereign claims over the legal status of the Chagos Islands, and Argentina's claims over the Falkland/Malvinas Islands. Former British colony Mauritius introduced a UN resolution to refer the dispute over the Chagos Islands to the ICJ in 2017. Unexpectedly, most EU member states abstained rather than support the UK, as they had done previously. The ICJ ruled that the UK's occupation is illegal and ordered the UK to return sovereignty over the islands to Mauritius (Guardian 2019), and the UN General Assembly passed a similar non-binding resolution, with most EU states abstaining or not supporting the UK, sending a clear message regarding Britain's colonial legacy and continued sovereignty claims (BBC News 2019b). Similarly, Argentina speculated that Brexit might cost Britain EU members' support in its dispute over the Falklands/Malvinas Islands, with the Foreign Minister asserting that Argentina stands ready to use Brexit to "enhance" its sovereignty claims over the islands (Politico 2018b). In 1982 during the Argentinian-British conflict over the islands, the UK had been able to successfully cast its actions as part of a status-quo power role rather than a colonial power role (McCourt 2011). The Brexit landscape, however, has allowed external actors to paint ongoing British sovereignty problems with the brush of its colonial past.
The UK's 2017 loss of a judge position on the ICJ is another instance where the UK's colonial role was invoked, with Indian newspapers comparing "Britain's be-haviour to its old commander in chief of British India" (BBC News 2017). An Iranian reaction to Brexit directly invoked UK colonialism, as Iran's Chief of Staff of the Armed Forces claimed: "England should pay the price of years of imperialism" and that Brexit would prompt payment in the form of dissolution of the UK state (Guardian 2016b). The UK's historical role as a colonial power is clearly relevant to the sovereignty-role nexus, with several actors offering a full-throated rejection of previous international sovereignty norms that legitimized colonialism (Philpott 1995(Philpott , 2001. These reactions to Brexit involve others invoking this historical role to discredit any behaviors associated with this negatively perceived sovereignty norm. Many interpreted Brexit as a reassertion of sovereignty in the EU (Wilson and Oliver 2019) and a dangerous precedent for further European disintegration, putting the "European project" itself at risk. PM Cameron warned of European conflict if the EU disintegrated, saying "The European Union has helped reconcile countries which were once at each others' throats for decades. Britain has a fundamental national interest in maintaining common purpose in Europe to avoid future conflict between European countries" (Cameron 2016b). Pope Francis was among many who worried that Brexit might prompt a "Balkanization" of Europe (Manila Times 2016). Auer (2017, 44), in his analysis of debates over EU sovereignty in Brexit, argues that "Brexit marks a serious setback to the ideal of a borderless Europe." Others saw Brexit as an opportunity for EU revitalization (Adler-Nissen, Galpin, and Rosamond 2017), not least in the area of security and defense (Martill and Sus 2018). For European Commission President Juncker (2017), Brexit put the "wind … back in Europe's sails." Junker proposed that the EU should "catch the wind" to further integrate around the Eurozone and the Schengen system: "We will advance, we must advance because Brexit is not everything. Because Brexit is not the future of Europe." Beyond stimulating renewed emphasis on European integration, Brexit highlighted the revolution in sovereignty norms represented by the EU project itself-that a supranational entity can hold sovereignty. French President Macron (2017) emphasized this point by detailing six keys to strengthening "a sovereign Europe." Whether Brexit will generate disintegration or integration is unclear, but that it has activated debates about pooled sovereignty and the regional system of European states is most evident.
The question of EU integration has a temporal-role dimension, as "… the historical self may play the role of the significant other" (Beneš and Harnisch 2015, 151;Wehner 2020). If Germany's civilian power role once represented a rejection of Germany's negative historical self in favor of anti-nationalist European institutions (Maull 2000), Brexit is much the opposite, with supporters pursuing a positive historical self and celebrating nationalism through de-institutionalization from the EU. Britain's historic great power role prescribes seeking more sovereignty in the present, but internationally this was seen as temporally anachronistic among the Commonwealth and former subjects, with its counter-normative proximity to colonialera norms of sovereignty.
Brexit has also been interpreted as threatening the broader, post-WWII liberal world order (Walt 2016;Fisher 2018), a sort of "Brexi-stential" crisis challenging liberal norms of sovereignty that encourage cooperation under anarchy. This was reinforced with Trump's election. As Adler-Nissen, Galpin, and Rosamond (2017, 580) note: "Trump argued that Brexit marked the beginning -or indeed the promise -of a new world order based on national independence and identities." Indeed, Trump (2017b) called for "a great reawakening of nations" and a world of "strong, sovereign nations," in contrast to what he saw as constrained sovereignty in the EU. This was another way that the Brexit role change implicated broad sovereignty norms within the international system.

Conclusions
US Secretary of State Acheson famously quipped in 1962 that "Great Britain has lost an empire and has not yet found a role" (Briggs 2016). The year prior, the UK had applied for EEC membership and was formally admitted more than a decade later. The UK played this EU member role for over forty years until the Brexit referendum again placed it into a profoundly uncertain international position. This "Brexit stage right," partly driven by the political right and populist sentiments and resisted by status quo-oriented international actors, has not yet reached its final act, as complex negotiations continue.
Not only is the UK government, as McHarg and Mitchell (2017, 520) argue, "caught in a classic two-level game, negotiating with competing domestic demands … and conducting negotiations with the EU27," the sovereignty-role nexus framework developed here sees it in a "two-level sovereignty game," wherein domestic and international conceptions of and concerns about sovereignty are simultaneously negotiated through role location. This creates challenges for the UK as it seeks a role change that satisfies domestic desires for more control while avoiding isolationism, is accepted by key international actors, and fits prominent norms of sovereignty consistent with both the liberal international order and anti-colonialism.
Role changes involving sovereignty concerns may be met with widespread skepticism for several reasons, hindering the translation of greater sovereignty into substantive foreign policy roles. Alters may resist Ego's role change if it challenges their own conceptions of, and commitments to, sovereignty. In the Brexit case, we saw this in reactions from the EU and key member states (such as Germany and France) and Brexit's perceived threat to pooled sovereignty and the European order. Others (such as Trump in the Brexit case), however, may support the role change because it advances their state-based conceptions of sovereignty. Resistance may also come from Alters who themselves face significant sovereignty concerns and may be particularly affected. These concerns may be with internal groups (as several European governments also faced Euroskeptic and populist opposition) or with their own sovereign roles and borders (such as Ireland's relationship with Northern Ireland).
More generally, these role changes may encounter existential resistance, since they have the potential to affect the larger normative context around sovereignty, upon which all roles are built. This may activate contestation and socialization across a wide range of actors who themselves have little material stake in Ego's role change. Reactions to Brexit invoked norms of sovereignty, with some actors emphasizing the value of existing norms around pooled sovereignty and liberal order, and others, such as India and Mauritius, stressing the negative value of previous colonial norms. Both anti-colonial and pooled sovereignty norms are key "revolutions in sovereignty" (Philpott 1995(Philpott , 2001 and the UK has uniquely struggled around both of these owing to its history as a colonial power and its late and partial commitments to European integration (Wallace 1986). Prevailing norms of sovereignty may be used as a disci-plining tool, restricting role changes that venture too near to sacred sovereignty norms (anti-colonialism) or too far from prevailing sovereignty trends (liberal order/European integration). The disciplining mechanisms reside in the processes of role socialization, which may take the form of "sovereignty skirmishes." Lingering questions about the sovereign status of Gibraltar and the Chagos Islands, potential Scottish independence, and the UK's lost position on the ICJ are examples from the Brexit case.
While Brexit is unique, the sovereignty-role nexus may be evident in other cases of role change. Novice states, for example, are a specific class for role socialization, as Thies (2013) has argued for the cases of early US and Israeli statehood. Beasley and Kaarbo (2018) extended this to aspirant states such as Scotland, arguing that novice and aspirant states are socialized into sovereignty and their new sovereign roles. Four other types of states may also experience sovereignty-related role changes.
First, postcolonial states emerged as part of a revolution in sovereignty norms and must balance their independent foreign policy roles against historical ties to former colonizers (Hansel and Möller 2015;Thies 2017). Given the significant impact of decolonization on the size and character of the international system, understanding the relationship between sovereignty and role-taking may lend insights into this global transformation. Second, defeated and highly dependent states, such as postwar Japan and Germany, Ukraine, and Chile, struggle to define and change their roles due to constraints on sovereignty placed by others (Chafetz, Abramson, and Grillot 1996;Brummer and Thies 2015;Hirata 2016;Wehner 2016). The ways such roles are shaped may reveal how dominant actors exercise power directly through the construction of sovereignty. Third, small states seeking role transformations face difficulties given that state size is related to conceptions of sovereignty (Gigleux 2016;Breuning 2018). Small states also frequently form through the dissolution of another sovereign state (Ingebritsen, Neumann, and Gstöhl 2012), potentially offering insights into the parallel construction of sovereignty and roles in relation to their parent state. Finally, states' decisions to seek new roles by joining or leaving international organizations and formal alliances will often involve fundamental questions of sovereignty, such as Switzerland joining the UN (De Vore and Stähli 2011), France leaving NATO's integrated military command in 1966 (Krotz 2015), and Mexico's signing of NAFTA (Below 2015). The perspective we have developed points future research toward examining the connection between internal contestation and external socialization in these types of role change.
Consistent with those who assert that role theory can bridge agents and structures (Barnett 1993;Thies and Breuning 2012), we have argued that states' roles and sovereignty are interwoven. Sovereignty norms within the international system at any given time shape what sorts of actors can hold sovereign roles, what powers they have to enact different roles, and what sorts of roles are available and legitimate to pursue. Role theory, in turn, gives us a distinct foreign policy perspective on the construction of international norms. Compared to other constructivist approaches to sovereignty, a role theory perspective emphasizes agency as actors seek to employ and contest different norms of sovereignty in order to adopt particular roles. Because roles incorporate sovereignty norms to prescribe and guide appropriate role behaviors, we can also see the social construction of sovereignty through the altercasting and socializing of states. This provides a different and more nuanced understanding of how sovereignty is constructed and how this shapes roles, intra-and inter-role conflicts, and the international role system. All of these aspects were evident and important in the Brexit case.
We have not set out to understand exactly how, or whether, the social constructions of sovereignty may have changed for different actors. However, discourses did frequently employ sovereignty in arguments about the nature and value of role change, and the connection between sovereignty and roles was expressed in different ways by different actors. When the dust settles, we suspect that there may be some perceptible and potentially lasting consequences for the way in which sovereignty is understood by different actors, at the international, domestic, or even everyday level (de Carvalho, Schia, and Guillaume 2019). For example, domestically, the contestation about the location of sovereignty has exposed tensions between parliament, government, and the public, and it has amplified frictions in the UK constitutional settlement. Internationally, Brexit has spawned clear affirmations of anti-colonialism, but it is also a challenge to post-Westphalian notions of pooling sovereignty beyond the nation-state and to the liberal order itself.
Meanwhile, the arrival on the scene of US President Biden adds a further twist to the Brexit story. A longstanding critic of Brexit and its architects in the UK, Biden has pledged to lead on defending the multilateral international order and can be expected to resist the challenge to liberal sovereignty norms that Brexit represents (Biden 2017). Biden's early remarks, as President-elect, moreover, suggest that he will make the UK's faithful ally role, and any prospect of a US-UK trade agreement, conditional on the UK reaching a deal with the EU to avoid a hard border between Northern Ireland and the Republic of Ireland (Economist 2020). The foreseeable shifts in US foreign policy (Biden 2020) deprive Brexit supporters of their most important international support, strengthen international opposition against UK role changes envisioned by Brexit (in particular in Ireland and the EU), and heighten the risks of the UK being cast in the role of isolate. Brexit puts the UK on a collision course with the role expectations of the Biden administration, and the change in US government stands to feed back into domestic UK debates about the value of any sovereignty gained through Brexit. When the final curtain falls, we may well see the UK in a new international role on the world's stage that will have lasting implications not only for its foreign policy, but also for the rest of the EU and others' roles in the international system. In whatever way this play concludes, Brexit's plot weaves well the tangled web of foreign policy roles and the social construction of sovereignty.