Nonstate actors, including terrorist groups, regularly launch attacks against states, often from within the territory of another state. When a victim state seeks to respond with force to such attacks, it must decide whether to use force on the territory of a state with which it may not be in conflict. International law traditionally requires the victim state to assess whether the territorial state is "unwilling or unable" to suppress the threat itself. Only if the territorial state is unwilling or unable to do so may the victim state lawfully use force. Yet there has been virtually no discussion, either by states or scholars, of what that test requires. The test's lack of content undercuts its legitimacy and suggests that it is not currently imposing effective limits on the use of force by states at a time when transnational armed violence is pervasive.

This Article provides the first sustained descriptive and normative analysis of the test. Descriptively, it explains how the "unwilling or unable" test arises in international law as part of a state's inquiry into whether it is necessary to use force in response to an armed attack. It identifies the test's deep roots in neutrality law while simultaneously illustrating the lack of guidance about what inquiries a victim state must undertake when assessing whether another state is "unwilling or unable" to address a particular threat. Normatively, the Article plumbs two centuries of state practice to propose a core set of substantive and procedural factors that should inform the "unwilling or unable" inquiry. It then applies those factors to a real-world example - Colombia's use of force in Ecuador in 2008 against the Revolutionary Armed Forces of Colombia - to explore how the use of these factors would affect the involved states' decisionmaking and the evaluation by other states of the action's legality. The Article argues that the use of these factors would improve the quality of state decision-making surrounding the use of force in important substantive and procedural ways.

Although liberal trade and development scholars disagree about the merits of the World Trade Organization (WTO), they both assume that WTO legal obligations restrict states' regulatory autonomy. This Article argues for relaxing this shared assumption by showing that, despite the restrictions imposed by international economic law obligations, states retain considerable flexibility to carve out policy autonomy.

The Article makes three distinct contributions. First, it analyzes how active WTO members can, through litigation and lawyering, influence rule interpretation to advance their interests. Second, the Article redefines the concept of "legal capacity" in the WTO context and introduces the term "developmental legal capacity," which describes how states can use legal tools and institutions not only as a sword to open new markets but also as a shield for heterodox economic policies. Third, the Article offers a comparative analysis of two case studies, Brazil and Mexico, and shows that they have pursued different trade and litigation strategies. While subject to the same WTO obligations, these countries have made different use of their policy space according to their own economic objectives. The Article concludes that, despite the apparent rigidity of the WTO, countries following a deliberate strategy can expand their regulatory space to advance their own interests.

The international criminal regime exhibits many retributive features, but scholars and practitioners rarely defend the regime in purely retributive terms - that is, by reference to the inherent value of punishing the guilty. Instead, they defend it on the consequentialist grounds that it produces the best policy outcomes, such as deterrence, conflict resolution, and reconciliation. These scholars and practitioners implicitly adopt a behavioral theory known as the "utility of desert," a theory about the usefulness of appealing to people's retributive intuitions. That theory has been critically examined in domestic criminal scholarship but practically ignored in international criminal law.

This Article fills this gap and argues that whatever its merits in the domestic realm, there are special reasons to be skeptical about the "utility of desert" claim in the international context. Moral intuitions as heuristics for moral judgments are error-prone, and the international criminal regime has a number of extraordinary features that may increase the likelihood and cost of these errors. These features include the complexity of the crimes; the diversity of stakeholders who possess heterogeneous intuitions; and the regime's multiple goals, some of which may be inhibited by moral condemnation. After examining these differences, the Article outlines the implications of the analysis for regime design. Some of these design implications accommodate the international criminal regime's current retributive approach, and some are fundamentally incompatible with retributivism.

How does global financial regulation work? I propose six principles that organize its current practice: 1) a national treatment principle, 2) a most favored nation principle, 3) a preference for rulemaking over adjudication, 4) a subsidiarity principle of enforcement, 5) a peer review model of enforcement, and 6) a network model of institutionalization. Most of these principles are shared by other institutions that meet the criteria of formal international law.

These emerging doctrines and institutional arrangements are stable, principled, and accordingly increasingly amenable to traditional legal analysis. While financial regulatory cooperation, as it is currently structured, is not the same thing as public international law, it exemplifies the parallel development of legal and other forms of state obligation. Moreover, analyzing global financial regulation as a law-like institution offers new insights into an increasingly paramount form of the regulation of finance, one that is likely to be a principal accomplishment of twenty-first-century international cooperation.

Bilateral investment treaties (BITs) are famously asymmetric. They grant investors rights but not obligations, while imposing upon states obligations unaccompanied by rights. Recent cases suggest, however, that BIT tribunals are poised to recognize a defense to state BIT liability that, in effect, imposes upon investors the obligation to avoid involvement in public corruption in the course of making a treaty-protected investment.

In this Essay, I sketch out the contours of this emerging defense, focusing on the recent investment treaty arbitration between Siemens AG and Argentina. Siemens was awarded over $200 million for Argentina's expropriation of its investment, but Siemens voluntarily abandoned the award in response to post-award revelations that Siemens had procured the investment through the systematic bribery of Argentine officials. While the Siemens tribunal never had the chance to rule on the legal consequences of the bribery allegations, jurisprudential trends suggest that it would likely have used the fact of corruption to either decline jurisdiction or to otherwise refuse to recognize Siemens's substantive treaty-based rights. I nonetheless argue that the specific contours of this emerging corruption defense are uncertain, and I suggest model investment treaty text for states that wish to secure their reliable access to it.