Harris introduces Walz; Vance speaks to supporters during Philly rallies: The Morning Rundown, Aug. 7, 2024

Vice President Kamala Harris introduces Minnesota Gov. Tim Walz as her running mate while Ohio Sen. JD Vance speaks to supporters during separate rallies in Philadelphia. And U.S. officials say a Pakistani national with ties to the Iranian government has been arrested in connection with a plot to kill American politicians. These stories and more highlight The Morning Rundown for Wednesday, August 7, 2024.