Judging by the number of published studies of multiple citizenship, one might be forgiven for thinking that nationalism and immigration were matters of marginal interest in contemporary democracies. Obviously a growing phenomenon in a globalized world, multiple citizenship has failed to interest political theorists in the way it has legal and globalization scholars. And yet the subject, as Ana Tanasoca notes in her new book, is located at the intersection of numerous growing debates in political theory: immigration and the boundaries of the demos; domestic and global justice; public deliberation in democracy; and commodification—in this case, of citizenship itself—with investments in the host country often being one path to obtaining citizenship.

Tanasoca has stepped into this gap in political theory with an innovative and heroic book: heroic because it aims to do away with the sharp dichotomy between citizen and noncitizen without turning away from the needs of democratic cohesiveness in emigrant and immigrant societies. She tries to bridge the gap between scholars who enthusiastically embrace multiple citizenship as heralding a postnational age and legal theorists who are queasy about the effects of postnational citizenship on citizen solidarity and citizen–state affiliation.

Rejecting multiple citizenship’s purported downgrading of the power of citizenship as a unique tie between individuals and a single state, Tanasoca cautions against its indiscriminate embrace. It may undermine the “democratic consensus legitimizing collective decisions” (p. 4), sustain rather than reduce global inequality (Chap. 7), and compromise more ambitious cosmopolitan projects that are “morally more justifiable and politically efficient” (p. 4) because multiple citizenship remains, like its mono-citizenship counterpart, a state’s privilege to grant or deny. It reinforces rather than negates the power of citizenship—albeit in more than one state—by reinforcing the link between citizenship and rights, on the one hand, and between noncitizenship and the lack of rights, on the other.

Tanasoca’s alternative is to “unbundle” the various rights now clustered under the umbrella of citizenship. She argues that only a subset of such rights should be available to immigrants seeking a second or third citizenship. The idea is to avoid “overinclusiveness” in emigrant societies by, for example, denying the vote to nonresident citizens. It can also decouple rights from citizenship, without creating second- or third-class citizens, by giving permanent-resident noncitizens voting rights because people ought to have a say in political decision making and political outcomes that affect them. Already, permanent-resident noncitizens may vote in regional elections in many countries and even in some national elections on the basis of denizenship. Tanasoca believes that this should be extended. Finally, and most radically, she argues that the category of citizenship itself should in some cases be abandoned in favor of a more flexible allocation of different subsets of rights and duties usually associated with it. People may then retain some rights in their country of emigration and others in the country of immigration without having citizenship in either. A powerful reason she offers for decoupling citizenship from rights is to render the business of giving rights to immigrants to facilitate their flourishing less fraught than offering them citizenship.

This is an ambitious book. Unsurprisingly, it is at its normatively most ambitious that it strains the expectation of its applicability in the “world-as-it-is,” to which Tanasoca herself alludes. Where it shines is in taking forward already-existing, if still-meager, notions of degrees of citizenship rights for different individuals. These can make immigrants’ lives a great deal easier and their treatment more just than the status quo without exposing them to the fraught national scrutiny that conferring citizenship brings. Thus, the idea that multiple citizenship should be active rather than passive—that it must be renewed periodically where one is nonresident and may come with a tax that compensates the emigrant society for the brain or financial drain—is a fine one. As it happens, it reinforces the importance of citizenship rather than diluting it, but that may not be a bad thing in itself.

The clearest difficulty with the book relates to its most radical and normatively ambitious proposal: the disappearance of citizenship altogether in some cases and the dispersal of different clusters of rights to different people in ways that would be too plural to become the locus of a politics of resentment and conflict. Tanasoca makes it clear that no immigrants would be naturalized. But existing birthright citizenships seems either to vanish or to be left untouched in the immigrant-receiving country, without much discussion, in ways that are reminiscent of the Marxist (lack of) discussion of the postrevolution world. Is birthright citizenship taken away through some explicit decree? If so, can birthright citizens be expected simply to acquiesce in this move even if citizenship has only symbolic value? If not, then how have we dealt with the dichotomy between citizens and noncitizens that Tanasoca tries to resolve?

Second, if birthright citizens remain citizens but without any distinguishing rights—the distinguishing hallmark of modern representative democracy has been the right to vote and run in national elections, after all—what is citizenship for? It has been clearly severed in this book’s conception from the demos, in that noncitizen voters are clearly part of the latter, justly so—but the question still remains.

Third, even if “citizen” becomes an empty honorific, it is a heroic assumption that the consequence would be to equalize citizen and noncitizen. It may do so in formal and variable rights so various that they permit no clear legal hierarchy of belonging. But there seems little reason for optimism that those who sported the honorific would not condescend to those without it, or not persecute them. To think otherwise is to underestimate the force of the narcissism of small differences around which people tend to show the most forceful propensity to engage in conflict.

On the question of retaining or forging democratic cohesiveness by rejecting overinclusiveness, Tanasoca assumes greater homogeneity than is warranted in both emigrant and immigrant societies. Her discussion of the “collective consensus” that legitimizes democratic decisions prompts one to ask whether and where this “consensus” exists—as opposed to legitimately contested claims. The range and degree of differences within a society, after all, are often as large as across societies, plurality is irreducible within groups, and differences across groups are often exaggerated, great as they may in fact be.

In addition, immigrants with multiple citizenships are no more of a threat to democratic cohesiveness than are contemporary, polarized, birthright citizens, divided by fragmented digital and social media and sharing few common narratives, mythologies, and frames of reference. Not just that. Emigrant, developing societies often welcome the purchase that a large diaspora with dual or multiple citizenship can and does bring them in tangible and intangible ways. The rich and more privileged emigrants who may buy citizenship certainly pose a threat to democratic integrity in receiving societies, but not in the ones from which they emigrate. Indeed, by wielding influence beyond their numbers in host societies where they may be part of elites of education or wealth, or constitute vote blocs, they may push immigration and citizenship policies in their new homes in ways that help the less privileged citizens of the countries they have left behind. The real loss to emigrant societies is the brain drain problem which, as writers such as Jagdish Bhagwati have pointed out, is best dealt with through taxation of emigrant citizens, which positively requires dual citizenship.

Finally, for a work deeply concerned with empowering noncitizens, the book seems not fully attentive to the possibility that immigrants may crave the citizen honorific more as a symbol of standing than for the vote which, after all, helps them only under highly contingent circumstances. If the struggles of groups that came late to citizenship in America—African Americans and women—are any guide, such groups value the standing that full citizenship brings much more than the right to vote. The latter was often viewed instrumentally, as the infallible insignia of full membership, not for its own sake. The chief virtue of The Ethics of Multiple Citizenship resides, then, not in the intricate solutions it offers. Rather, it consists in its challenge alike to facile postnationalist celebrations of multiple citizenship and to the sacrosanct status that citizenship has assumed in democracy, both classical and modern.