This essay is to be filed as a sub-category under the greater question of what sets the odds for international cooperation. It takes a closer look at domestic politics’ influence over the issue area: utilizing a liberal rational actor theoretical approach with an interest focus. The subject of this single case study is climate politics in the United States during the Obama Administration and its meaning for the Copenhagen Accord commitments.It concludes that domestic politics matter for the odds of international cooperation in the case of U.S. climate action and that ratification of the U.S. commitments to Copenhagen rest in the hands of strong interest groups. This conclusion relies on the fact that in the U.S., the decision-making horizon for the ‘collective’ of government branches is short due to overlapping election cycles, a slow legislative process and a weak party structure. What this essay underlines is that ignoring domestic politics and viewing states as unitary actors under conditions of divergent policy preferences between branches of government will produce incomplete and incorrect conclusions about the reasons and odds for international cooperation.