It was made clear at the December 2009 conference on climate change in Copenhagen (Conference of the Parties 15) that the nations of the world are only beginning to concede that they face a common threat. It was widely reported that there was a deep divide at Copenhagen between delegates from “developed” countries and delegates from “developing” countries, and that the depth of the anger of the delegates from developing countries surprised the delegates from developed countries. Should the anger have been surprising? Not only had some of the developed countries – most notably, the USA – failed to take significant steps prior to the meeting to reduce the impacts of their economies on the climate. In addition, the developed countries had come to the meeting to revise the global structure of climate change mitigation such that all countries (or at least all of the major economies) would share the task. This arrangement, all conceded, entailed a sharp departure from the previous structure, in place since the 1992 United Nations Framework Convention on Climate Change, which dealt with equity across nations by dividing the world into two groups of countries with “common but differentiated responsibilities.” Only the group of “Annex 1” countries (approximately, the countries of the Organization for Economic Cooperation and Development plus Russia) was obligated to make legally binding mitigation commitments.