Vaccine hesitancy is a major reason that many experts now fear the United States will struggle to attain herd immunity against the coronavirus. And while many initially hesitant demographics have become more open to vaccinations, one group is shifting much less: white Republican evangelical Christians, who tend to live in rural communities. Here’s what that looks like in Greeneville, Tenn. Guest: Jan Hoffman, a reporter covering behavioral health and health law for The New York Times.