The social contract tradition’s promise of facilitating just interaction among large groups of strangers remains as salient as ever. Kant in particular recognised that economic activity imposes costs on large and unspecifiable groups of people who cannot be asked in advance for their consent; he concluded that in order to engage in economic activity while dealing ethically with everyone, we require the state and the rule of law to set out the norms under which we can engage in other-affecting activity like commerce. In response to the challenge of coordinating the welter of anonymous interactions that modern economic life consists in, contract theory offers the social conventions of money and law.
However imperfectly these conventions operate in practice, people rely on them to orient themselves in the world. Carbon taxes have been touted by economists for decades as the most efficient way to send appropriate signals to people about their emissions behavior. The widely underappreciated fact that most fuel for international air travel remains untaxed—and is thus effectively subsidized relative to the rest of the economy—provides an especially vivid illustration of the necessity for appropriate social conventions to provide the conditions under which economic activity can be undertaken with less injustice.
In this paper, I explain why people seeking to flourish together fairly in the imperfect world we share today ought to support a universal carbon tax with no exception for international aviation. The argument proceeds in four steps. First, I provide a free-standing analysis of emissions behavior at the individual moral level. Second, I offer a picture of ideal and non-ideal coordination based mostly on Kantian social contract theory. Third, I argue that in a non-ideal context, moral signals about right relation offer a coordinating fulcrum around which meaningful if only partly coordinated action is possible. Fourth, I apply these conclusions to the case of aviation exceptionalism, focusing especially on instances of incomplete, overlapping, partly coordinated climate actions. I conclude that these arguments together amount to a case for reversing the Chicago Convention and applying a universal carbon tax that does not exclude international flights, ending aviation exceptionalism.