The U.S. Secret Service was under intense scrutiny on Sunday after a gunman managed to evade its agents and open fire on former President Donald Trump at a political rally, with Republican leaders vowing swift investigations and President Joe Biden calling for an independent review. The gunman, a 20-year-old Pennsylvania man, injured Trump and killed a rally attendee from a rooftop perch around 150 yards (140 m) from the stage where the former president was speaking in Butler, Pennsylvania,...