Trump Threatens to Close Borders; Bombshell Climate Change Report Released; Interview With Iowa Senator Joni Ernst; Interview With California Congressman Adam Schiff; Trump, Chief Justice Spar Over Judicial Independence; GOP Senator In Mississippi Under Fire For Confederate Ties; White House Releases Dire Climate Report Over Holiday Weekend; Obama Praises Beto O'Rourke As 2020 Campaign Heats Up; Interview With House Minority Leader Nancy Pelosi. Aired 9-10a ET