Jonathan Metzl, professor of sociology and psychiatry at Vanderbilt University and director of its Department of Medicine, Health, and Society and the author of Dying of Whiteness: How the Politics of Racial Resentment Is Killing America's Heartland (Basic Books, 2019), talks about the sharp resistance to gun control measures in red states, while at the same time guns are now the leading cause of death for children in the United States.