This is part of Hello, Trumpworld, Slate’s reluctant guide to the people who will be calling the shots now—at least for as long as they last in Washington. The “again” in Robert F. Kennedy Jr.’s rallying cry is what makes it so sickening. Make America Healthy Again? Like when we had more measles and malnutrition and cervical cancer? Obviously, MAHA is a suck-up to Trump and the white-nationalist “again” in MAGA. It’s also an appeal to the powerful force of nostalgia. It echoes the wellness-grifter ethos: vague, aspirational, anything-natural-is-good nonsense sold with a slick catchphrase. Kennedy is worse than that,...