This article presents a neoclassical realist theory of climate change politics that challenges the idea that cooperation on climate change is compelled alone by shared norms and interests emanating from the international level and questions if instead material factors also play a significant constraining role. The author compares the latest data on the magnitude, distribution and financial ‘additionality’ of climate funds and carbon markets to test his theory. Climate funds are found to be more vulnerable to systemic forces identified by neoclassical realism because they are largely drawn from existing official development assistance budgets despite international commitments that funds are ‘new and additional’. The study concludes that, while imperfect, carbon markets have too often been unfairly compared with an ideal climate finance mechanism that assumes few political constraints on international resource transfers for climate change.