Why was an agreement with the same essential characteristics rejected in Copenhagen and accepted in Paris? What changes between 2009 and 2015 led to the adoption of the specific agreement currently in force? In summary, U.S. climate negotiators only harmonized national and international policy contexts in 2015. Given the importance of the United States to the effectiveness of the regime, this mis-orientation has hindered the development of the regime. President Clinton struck an international agreement, but ignored a clear declaration of national interest by Congress. President Bush was not interested in pursuing an international agreement on climate change. President Obama actively attempted to address his domestic and international challenges and eventually managed to organize the international negotiation process in such a way that he could circumvent Senate ratification at home. Most importantly, he has put in place the necessary support from K-Group, especially from China, to a deposit and verification system that would avoid any legal obligation for the United States. Table 1 summarizes the two-step game analysis. Figure 5 shows the combined effects of the two-level game and the group argument k. National actors with divergent interests often try to influence the negotiator. While the domestic public has only limited influence over the negotiations themselves, their cooperation is often needed to ratify and implement a negotiated agreement. For example, in the United States, the Senate has the exclusive power to ratify an international agreement that sets out new legal obligations for the country. This demand puts the Senate in a powerful position to block the president`s interests.
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