Goldsmith and Posner (who use neoliberal models [i.e., game theory, etc] and approaches toward neorealist ends) in their article claim that customary international law is not an exogenous influence on states' behavior andthat states sometimes engage in behavior that only appears to be norm-following, but in reality is merely a coincidence of interests. What is their evidence (especially look at their 3 cases of (1) - neutrality and the doctrine of Free Ships, Free Goods, (2) diplomatic immunity, and (3) maritime jurisdiction and the territorial sea) and do you find it persuasive or not? Are they correct (and even if they are, does it matter)? And what are the strongest and weakest of their arguments in their view of the nature of international law?

Reference: Posner and Goldsmith, A Theory of Customary International Law, University of Chicago Law Review, Vol. 66(4) (Autumn 1999), pp. 1113-1177