A growing number of Democratic lawmakers are calling for Twitter and Facebook to pull down an edited video of House Speaker Nancy Pelosi (D-Calif.) that was posted by President Trump on Thursday, reigniting a battle over how much responsibility social media platforms should assume over viral footage that could mislead viewers. The back-and-forth over the Pelosi video is opening up fresh wounds, as Democrats are still incensed by Twitter and Facebook's previous decision to leave up a different manipulatively edited video of Pelosi that went viral last year. Pelosi's deputy chief of staff, Drew Hammill, on Friday said the "latest...