This paper assesses the potential for an emergency DAC deployment program to slow and reverse the rise in atmospheric CO2 and global mean temperature. First, it estimates the financial resources that might be available for emergency deployment, grounding that in political theories of crisis decision-making. Second, it builds a bottom-up deployment model that constructs, operates, and retires successive vintages of DAC plants, given available funds and the rates at which DAC technologies might improve with experience. Such a model must include constraints on the speed with which novel industries can scale and must also characterize the costs and emissions from the many types of energy supplies (heat and electricity) that could power DAC. Third, it links the political and techno-economic modeling of the first two components to climate models that estimate the effects of these deployments on the carbon cycle, atmospheric CO2 concentration, and global mean surface temperature.