As early as Tuesday, House Oversight Committee Chairman Rep. Elijah Cummings could subpoena a top White House official over the issue of security clearances. A whistleblower told the committee that dozens of people in the Trump administration received security clearances despite "disqualifying issues." Also, host Robin Young speaks with Frank DeAngelis, the principal of Columbine High School in 1999, when two students killed 13 people in a shooting rampage. That and more, in hour one of Here & Now's April 2, 2019 full broadcast.