The volleys started when Carlson, in a nearly 14-minute segment, included Duckworth’s answer on CNN over the weekend when she was asked whether she also supported removing monuments honoring historical figures in U.S. history who were slave owners, such as George Washington. In her response, which went on to criticize President Donald Trump’s recent appearance at Mount Rushmore, Duckworth said there should be a national dialogue on the issue at some point. When pressed, Duckworth said, “I think we should listen to everybody.” On his show Monday night, Carlson noted that Duckworth is among the contenders to be Democrat Joe...