Rationing occurs in the United States. Anyone on a waiting list for a kidney or liver transplant knows this. But in just two weeks, the need to select which severely ill coronavirus patients will receive treatment — and which will go without — will be more acute than anything Americans have ever experienced or probably imagined. Even in the most favorable scenario, 39,727 intensive-care-unit beds will be needed on April 15, the projected peak date for the covid-19 pandemic in this country. Only 19,864 such beds will be available. There won’t be enough ventilators, either. These projections, from the Institute for Health Metrics and Evaluation at the University of Washington, optimistically assume that social distancing measures are maintained for weeks. The actual shortfalls are likely to be worse.