In an NPR exclusive interview, President Trump's former National Security Adviser John Bolton told Steve Inskeep that he doesn't believe that North Korea will ever give up its nuclear weapons program by way of negotiations with the US. Seven of the leading Democratic presidential candidates came together outside Los Angeles for the most contentious debate of the campaign season so far. And Australia has been enduring its hottest recorded temperatures in history this week, as hundreds of bushfires continue to devour large areas around Sydney.