Sharing Territories is an ambitious and timely contribution to the contemporary philosophical debate on territorial rights. Nine's work highlights the robust interdependence of individuals and groups living within spatially interconnected resource domains such as river catchment basins and urban areas, arguing that the residents must collectively manage these domains through novel jurisdictional units that may overlap with existing state boundaries. The book raises the bar for the level of normative rigour and detailed institutional design we should expect from political theorists considering issues of international natural resource management, collective self-determination, and natural interdependence, especially those considering these issues in light of the global climate and environmental crises.
Territorial rights are moral rights—usually thought to be possessed by a state or a people—to make and enforce laws for a geographically demarcated region of the earth and those who are physically present on that territory. A challenge for territorial rights theorists has been identifying the normative considerations that justify the exercise of territorial rights by a particular agent over a particular place. Drawing on Pufendorf's theory of natural law and contemporary feminist theories of relational autonomy, Nine argues for a set of “foundational titles”: individual use rights to objects and resource domains that ultimately “anchor” territorial rights in particular locations. These foundational titles include natural rights to access and use territorial resources and systems upon which we rely to meet our basic needs and which we incorporate into our legitimate activities; rights to our home as a particular physical dwelling upon which we rely to maintain the coherence of our identity and our agency over time; and rights to access important social spaces within which we develop and exercise our autonomy according to a wide set of identities, obligations and roles. The clarity with which Nine develops her account of foundational titles is an important accomplishment; much too often these considerations are not sufficiently differentiated from one another in theories of occupancy rights, ignoring distinctions to be made among the precise ways in which persons are attached to particular places and resources, as well as the rights and obligations that follow from specific relationships to land.
Building on her theory of foundational titles, Nine argues that people living in densely physically integrated areas, such as cities and river basins, cannot live together in ways that respect each other's place-specific rights and obligations without a common set of political institutions to govern their activities in that place. This is exemplified most clearly in the case of water management policy, where the decision to build a dam upstream to produce hydroelectric power in one country might limit the flow of water and nutrients downstream, in turn adversely affecting the ability of citizens in another country to access water for agricultural or industrial activities. In cities, decisions about the location of industrial sites have knock-on effects on the location of residential housing and educational services, affecting various personal obligations, relationships, and life plans. Importantly for Nine, actions within these regions may affect others’ moral agency—that is, their capacity to develop and perform personal obligations within a broad range of social, political, familial and professional spheres of life. Therefore, Nine argues that within these densely interconnected and scaffolded regions, residents are obligated to co-ordinate with each other to develop a common set of institutions to specify rules to manage conflicts in ways that respect the natural rights and equal moral agency of everyone. Correspondingly, Nine argues that these “foundational territories” possess a complex set of rights and responsibilities, including immunity to division by higher-order units, pre-emptive jurisdictional authority over matters pertaining to the co-ordination of place-based natural use rights and obligations, and shared metajurisdictional authority—the right to negotiate their precise remits and competences vis-à-vis other political units.
Nine's theory is to be especially commended for the nuance and depth with which it constructs the relationship between foundational territories and larger configurations of territorial power. For Nine, foundational territories are the building blocks of larger territorial units such as states and sometimes will straddle two or more existing states. Accordingly, her theory places determinate limits on the jurisdictional and metajurisdictional powers of states without rendering states themselves obsolete. Central to Nine's argument here is a conception of “functional autonomy,” wherein the self-determination of political units within complex interdependent systems is to be measured according to their performance of specific political functions. This “logic of achievement” makes up part of Nine's proposed “narrow principle of subsidiarity” for regulating negotiation and mediation between foundational territories and other political units such as states. Within this context, the self-determination of political units is not to be viewed as inconsistent with relationships of dependence, but rather, in some cases, to be facilitated through an overarching division of responsibilities and resource transfers.
It is certain that Nine's book will provoke much debate within territorial rights and environmental management discourses. On the empirical side, one especially important question concerns the specific governance solution for overlapping resource use and mutual obstruction that she recommends. For Nine, domains such as the Great Lakes and the Windsor–Detroit region are clear examples of integrated domains requiring a unified jurisdictional unit to promulgate common policies for resource management; however, it is not certain from her analysis why bilateral commissions or international treaties are insufficient to achieve the required degree of co-ordination. Further empirical analysis of existing strategies and institutions (such as the International Joint Commission) might bolster Nine's argument that a novel jurisdictional approach is required. On the theoretical side, Nine's occasional description of her theory as a species of legal pluralism will be debated. It is not clear that legal pluralism as she conceives it, where “multiple systems of law produce different systems of rules for acting on the same issue” (12, 213), can serve to reduce resource use conflict and mutual obstruction—the problems justifying the novel unified jurisdictional unit in the first place—or that she need be committed to such a conception for her argument to function. Finally, proponents of other camps within territorial rights theory are sure to balk at Nine's diminished role for considerations of political identity, nationhood or culture; further consideration of how these would intersect with complex international governance regimes for shared territories will surely be spurred on by her compelling and rigorous argument about the overlap and interdependence of groups.
