Overnight Defense: Esper sworn in as Pentagon chief | Confirmed in 90-8 vote | Takes helm as Trump juggles foreign policy challenges | Senators meet with woman accusing defense nominee of sexual assault

THE TOPLINE: Mark Esper was sworn in as Defense secretary on Tuesday evening, officially ending the Pentagon's longest-ever period without a Senate-confirmed leader.The swearing-in, conducted by Supreme Court Justice Samuel Alito in the Oval OfficE...