For over half a century, medical guidance from the United States has shaped public health decisions worldwide. At that moment in 2020, it seemed almost incomprehensible that an American president could be dispensing advice so evidently lethal and nonsensical that even a middle schooler would know not to follow it. In his second administration, the president’s alliance with Robert F. Kennedy Jr. has plunged the American public health apparatus into its vibes-based era, in which evidence-based medicine needn’t factor into decisions of enormous significance. “Don’t take Tylenol,” President Trump advised pregnant women over and over, referring to the brand name for acetaminophen. The Coalition of Autism Scientists, comprising top research scientists in the field, quickly released a statement, saying the press conference “alarms us….