Addressing global climate change through the regulation of greenhouse gas emissions is an issue of broad national and international concern, touching on many facets of this country's environmental and economic well-being. Crafting a workable solution will require a coordinated and comprehensive approach, for only such an approach will maximize the environmental benefits of regulation while not imposing undue costs on already strained American businesses and consumers. Developing a Comprehensive Approach to Climate Change Mitigation Policy in the United States: Integrating Levels of Government and Economic Sectors by Peterson, McKinstry, and Dernbach highlights two threshold questions that policymakers face in addressing greenhouse gas regulation. First, given that federal action to address greenhouse gas emissions is a virtual certainty, what role should be left for states and localities to play? Second, in crafting a federal response, do the existing authorities under the Clean Air Act provide a workable framework for greenhouse gas regulation, or is a new regulatory regime required?

On the first question, Peterson et al. suggest that states will continue to play a significant role in shaping climate change regulation in conjunction with federal action. The authors' conclusion, however, begs the threshold question of which level of government--the state governments or the federal government­is best suited to enact requirements addressing climate change that balance the various competing interests and reach the optimal level of stringency.