The framework highlights the dilemma of the international negotiator, who must balance the requirements of several largely independent target groups: other negotiating states (level I) and domestic policy actors (level II). Conditions at both levels can change over time, providing opportunities and restrictions for the negotiator. In this document, I refer to the President of the United States as a “negotiator.” Finally, the success of the Palestinian Authority would have been impossible without the failure of Copenhagen (Rajamani Reference Rajamani2011; Dimitrov Reference Dimitrov2016; Reference Park2016). COP15 and COP21 were not independent events, but steps in a path-dependent trajectory, fuelled by lessons and reactions to past experiences. The dramatic experience in Copenhagen drew attention to international climate policy at the highest political level and laid the foundations for the substance of the Palestinian Authority (Bodansky Reference Bodansky2016a). The Copenhagen agreement was rejected in 2009, but most of its physical provisions were expanded and formally adopted in Cancun in 2010, framing the textual negotiations that began with the Durban Platform decision in 2011. The KP was another important point in the development of the current climate regime. While many of the principles, processes and institutions that continue to characterize the climate regime have been defined, its central logic and its main characteristic – mutually agreed emission reduction targets – were then used as an example of how Pa pa cannot be conceived. Rational institutionalists are not surprised by the diplomatic breakthrough of 2015. From their point of view, structural concerns persist in the world after Paris, despite major changes in the structure of incentives for climate action. Some continue to explore the benefits of climate clubs or mini-nationalism (Falkner Reference Reference Falkner2016a); others doubt the potential effectiveness of the Palestinian Authority (Keohane and Victor Reference Keohane2016; Keohane and Oppenheimer Reference Keohane and Oppenheimer.2016). Despite these trends, the Senate remains an important national constituency for the presidential negotiator.

Given the stability of 20 years in the Senate`s opposition to new international commitments, the difference between the outcome of the UNFCCC negotiations can only be explained by the evolution of the negotiating strategies of the various presidents of the United States since 1997 and by possible changes at Level I. The following sections analyze these two dynamics and their interweaving over time. In response to these internal political constraints, President Obama committed to the deposit and verification system in Copenhagen in 2009 and Paris in 2015. Its negotiating objectives, U.S. federal policy and key elements of the negotiated treaty remained stable during this period and do not explain why one conference failed and the other was successful.