Bill Bryan, the head of the Department of Homeland Security’s science and technology division, had just made the seemingly innocuous remark that “the virus dies the quickest in the presence of direct sunlight.” This was Trump’s cue to offer some intriguing scientific hypotheses. “So supposing we hit the body with a tremendous—whether it’s ultraviolet or just very powerful light—and I think you said that hasn’t been checked, but you’re going to test it,” he said,
