A month after a gunman killed 22 people at a Walmart store in El Paso, the nation’s largest retailer, said that it would stop selling ammunition used for handguns and military-style weapons and call on Congress to consider a new ban on assault rifles. We look at what Walmart’s move means, and how corporate America could play a role in curbing the epidemic of gun violence. Guest: Andrew Ross Sorkin, a financial columnist for The New York Times. For more information on today’s episode, visit nytimes.com/thedaily.  Background reading: Walmart, whose reach has reshaped communities nationwide, largely avoids publicly wading into politics. That made its decision to limit ammunition sales even more notable.The move by Doug McMillon, Walmart’s chief executive, “to engage in a meaningful conversation about responsible gun sales in America could give license to other business leaders to enter the conversation,” Andrew Ross Sorkin writes. For more information on today’s episode, visit n...