CUSTOMARY INTERNATIONAL LAW coalition of states with convergent interests) forces or threatens to force other states to engage in acts that they would not do in the absence of such force. Although we take no position on how the labelCiL "ought to be used, scholars who use this label to refer to behavior arising from coincidence of interest or coercion usually are under the erroneous impression that the behavior reflects successful international cooperation Third are cases of true cooperation. These cases are best modeled as a bilateral iterated prisoners dilemma in which two states receive relatively high payoffs over the long term as long as both states resist the temptation to cheat in the short term If certain conditions are met, the resulting behavioral regularity can be one in which the higher payoffs are obtained. Fourth, some behavioral regulariti associated with CIL can arise when states face and solve bilateral coordination problems. In these cases, states receive higher payoffs if they take identical or symmetrical actions than if they do not. Both cooperation and coordination can be robust in bilateral contexts, but will not likely occur in multilateral contexts The theory suggests that most international behavioral regularities associated with CIL reflect coincidence of interest or coercion. These cases are trivial and have no normative content for states independently pursue their self-interest without generating gains from interaction. The theory also contemplates that some international behavioral regularities associated with CIL will reflect cooperation or coordination, but the theory suggests that these egularities will arise in bilateral, not multilateral, interactions. What appear to be multilateral CIL norms, then, are illusions, the product of some combination of (a) coincidence of interests among all, or almost all, states, (b)coercion by one or a few powerful states, or(c) a prisoner's dilemma or a coordination game played out in discrete bilateral contexts This theory differs from the standard conception of CIL in several fundamental respects It rejects the usual explanations of CIL based on opinio juris legality, morality, and related concepts. States do not comply with norms of Cil because of a sense of moral or legal obligation; rather, their compliance and the norms themselves emerge from the states pursuit of self-interested policies on the international stage. In other words, CiL is not an exogenous force3 CUSTOMARY INTERNATIONAL LAW coalition of states with convergent interests) forces or threatens to force other states to engage in acts that they would not do in the absence of such force. Although we take no position on how the label “CIL” ought to be used, scholars who use this label to refer to behavior arising from coincidence of interest or coercion usually are under the erroneous impression that the behavior reflects successful international cooperation. Third are cases of true cooperation. These cases are best modeled as a bilateral iterated prisoner’s dilemma in which two states receive relatively high payoffs over the long term as long as both states resist the temptation to cheat in the short term. If certain conditions are met, the resulting behavioral regularity can be one in which the higher payoffs are obtained. Fourth, some behavioral regularities associated with CIL can arise when states face and solve bilateral coordination problems. In these cases, states receive higher payoffs if they take identical or symmetrical actions than if they do not. Both cooperation and coordination can be robust in bilateral contexts, but will not likely occur in multilateral contexts. The theory suggests that most international behavioral regularities associated with CIL reflect coincidence of interest or coercion. These cases are trivial and have no normative content, for states independently pursue their self-interest without generating gains from interaction. The theory also contemplates that some international behavioral regularities associated with CIL will reflect cooperation or coordination, but the theory suggests that these regularities will arise in bilateral, not multilateral, interactions. What appear to be multilateral CIL norms, then, are illusions, the product of some combination of (a) coincidence of interests among all, or almost all, states, (b) coercion by one or a few powerful states, or (c) a prisoner’s dilemma or a coordination game played out in discrete bilateral contexts. This theory differs from the standard conception of CIL in several fundamental respects. It rejects the usual explanations of CIL based on opinio juris, legality, morality, and related concepts. States do not comply with norms of CIL because of a sense of moral or legal obligation; rather, their compliance and the norms themselves emerge from the states’ pursuit of self-interested policies on the international stage. In other words, CIL is not an exogenous force