The provision of global public goods — for the common defense, the economic development of the world’s poorest societies, and the mitigation of and adaptation to climate change — is at risk as governments in Europe and the United States try to rein in their spending to cope with the mounting public debts incurred during the Great Recession. Such fiscal austerity threatens the long-term security, humanitarian, and environmental interests of nations on both sides of the Atlantic. Looming austerity will require defense cooperation heretofore not seen in peace time. Greater cooperation in research and development, production, and procurement of defense technologies would be a logical move for cash-strapped NATO allies. Foreign aid is likely to be another casualty of fiscal belt-tightening. A pooling of American and European aid funding at the country or regional level may be necessary to cope with limited resources. Climate finance needed for adaptation to and mitigation of climate change is similarly at risk. New and innovative sources of financing are desperately needed. It is time for a transatlantic dialogue on the implications of fiscal austerity for global public goods.