The Trump administration is waging a ‘wholesale assault on U.S. science’ that threatens the country’s health, economic development, national security and scientific preeminence. That's according to an open letter published by nearly 2,000 doctors, scientists and researchers. William Brangham discussed the letter with Dr. Steven Woolf, one of its authors. PBS News is supported by - https://www.pbs.org/newshour/about/funders