WAMC's Dr. Alan Chartock discusses the Saturday shooting where one person died and three others were injured at a California synagogue. He also comments on President Trump's withdrawal from a global arms treaty via a speech to the National Rifle Association on Friday. Also in the headlines: a UN report will likely call for a "nature rescue plan," and Democratic Rep. Jerry Nadler has threatened to subpoena Attorney General William Barr if he refuses to testify this week.