Photo: Tierney L. Cross/Bloomberg/Getty Images The most damaging question for Robert F. Kennedy Jr. on the first day of his confirmation hearings to be secretary of Health and Human Services wasn’t about his anti-vaccine views or past embrace of conspiracy theories. It was about how Medicare and Medicaid work. After pointed questions from Democrats, he seemed relaxed when Republican Bill Cassidy, an unprepossessing physician from Louisiana, took his turn. Kennedy had no suggestions for how to