This Article argues that in the Kosovo Opinion, the International Court of Justice assiduously asserted its own jurisdictional, interpretative, and institutional prerogatives, at the cost of avoiding the momentous questions about secession and self-determination with which the Court was so clearly confronted. These two outcomes are related: The avoidance of substance and the assertion of prerogative were achieved by the selfsame maneuvers of definition and interpretation. Faced with a choice between emphasizing its own authority and actually engaging the question, the Court chose to invest in itself—but it did not, in turn, use that investment to any substantive end. The Opinion exhibits a misplaced boldness, advancing its procedural agenda but saying—almost literally—nothing in the process.

This Article also considers what a bolder Opinion might have looked like, by comparing the Opinion to the Canadian Supreme Court's seminal Reference re Secession of Quebec. This comparative exercise helps us to understand why questions of self-determination are easier to avoid than to decide—why it is hard even to talk about them in coherent and productive terms, and thus why one must feel sympathy for the seemingly impossible task facing the ICJ—but also to see that another, bolder language is in fact possible.

Part I addresses the treatment of extraterritoriality across these three countries. Part II does the same for extranationality. These comparative law analyses pay special attention to the sources of the legal regimes and to the similarities and differences among the three countries' approaches. But comparative law is not only a tool to evaluate extraterritoriality and extranationality separately; it is also a tool to compare approaches toward foreign affairs with approaches toward indigenous peoples—here embodied in a presumption against extraterritoriality and a presumption in favor of extranationality. Part III takes up this task, focusing on sovereignty, separation of powers, and due process in the context of these rules. Finally, Part IV identifies practical lessons drawn from the manifold approaches to these related issues. In sum, this Article launches a new double-comparative enterprise and, in the process, offers policy proposals derived from the study of the American, Canadian, and Australian approaches to extraterritoriality and extranationality.