Computer modeling technologies have increasingly become part of the conduct of science, public policy making, and the practice of politics. Their contribution to the world can be understood as intellectual, scientific, forecasting, governmental, truth production, and political technologies. This article focuses on the ways in which computer modeling has reconfigured the world of politics as illustrated in a case study of the use of economic modeling in the politics of Australia’s greenhouse gas emissions policy. From 1997, the Australian government pursued a policy of increased greenhouse gas emissions supported by computer modeling that forecast significant negative economic impacts on the Australian economy if emissions were reduced. These modeling results were publicly contested. The case study illustrates how computer models can be used in politics to construct a partisan point of view. It is argued that despite differences in the political use of computer models, their growing complexity constrains the capacity for the conduct of democratic politics.