The long-running feud between Jeb Bush and Donald Trump escalated yet again Saturday, with the former Florida governor releasing a two-minute video on social media mocking the billionaire's fitness to be commander-in-chief. *snip* The clip is the latest salvo in the Bush-Trump rivalry, which has often been marked by bitter and personal exchanges between the two prominent Republican presidential candidates. On Friday, Trump suggested Bush's brother, former President George W. Bush, shared in the blame for the 9/11 terrorist attacks because they occurred during his presidency. Saturday's round centered on a video set to the tune of circus music that...