Abstract
Why do governments sometimes exercise unilateral leadership in international environmental cooperation, such as the mitigation of global climate change? It is usually the case that unilateral leadership cannot solve the problem at hand, so it is not clear what the benefits of unilateral leadership are. In this article, I provide a new political rationale for unilateral leadership. I show that if a green politician (worried about environmental destruction) fears that he or she will probably lose power soon, he or she may want to unilaterally implement domestic mitigation policies to reduce the domestic cost of mitigation in the future. By exercising unilateral leadership, this politician ensures that even a future brown politician (only mildly interested in environmental protection) is, due to the domestic cost reduction, willing to engage in international cooperation. The findings imply that while unilateral leadership is not a panacea, it may be a useful commitment device under empirically plausible conditions.
Acknowledgments
I thank Andrew Cheon, Ram Fishman, the anonymous reviewers, and the editors of International Interactions for valuable comments and advice.
Notes
1To be sure, the technology coefficient may be higher than the learning curve indicates because the marginal cost of additional clean technology increases as the most lucrative market niches have already been used.
2It is not necessary to analyze green-brown and brown-green separately because the model is symmetric.
3Given that the United States Senate failed to pass federal climate legislation prior to the 2009 Copenhagen conference, the European Union was nonetheless unable to “seal the deal” for a global climate treaty to follow the Kyoto Protocol after the year 2012. This failure is consistent with the model, as the benefits of unilateral leadership are probabilistic.