The Kennedys have long been considered America’s royal family, and for generations, they’ve been brought up in the great state of Massachusetts. That includes Robert F. Kennedy Jr., the current Health and Human Services Secretary—but his latest idea to improve the health of Americans could burn the bridge with his home state for good. At a recent rally in Austin, Texas, Kennedy drew a line in the sand against one of Massachusetts’ most beloved brands: Dunkin’ (formerly Dunkin’ Donuts). Kennedy said he planned to press coffee chains including Dunkin’ for proof that their ingredients were safe for consumption, particularly in terms of sugar content. “We’re going to ask Dunkin’ Donuts and Starbucks, ‘Show us the safety data that show that it’s okay for a teenage girl to drink an iced coffee with 115 grams of sugar in it,’” Kennedy said. “I don’t think they’re gonna be able to do it.” Naturally, Bay Staters weren’t having it.…