A researcher at Columbia University who studies atmospheric and climate science gives a first-hand account of what it is like to pursue this work in the Trump 2.0 era, when the foundations of American science are being profoundly shaken. The post-World War II traditions that have made American science so successful—generous funding, awarded based on merit via peer review; academic freedom; openness to foreign talent; and most of all, systems of funding and executing science that are largely run by scientists, rather than by politicians—are under siege. What comes next is still an open question.