Secretary of State Rex Tillerson said he’ll use a meeting this week in Moscow to challenge Russia about chemical weapons in Syria, as the Trump administration plans its next moves following a missile strike in retaliation for the Assad government’s use of the banned munitions. Russia “agreed to be the guarantor of the elimination of the chemical weapons, and why Russia has not been able to achieve that is unclear to me,” Tillerson said Sunday on ABC’s “This Week” program. Tillerson, National Security Adviser H.R. McMaster and United Nations Ambassador Nikki Haley all appeared on Sunday talk shows to discuss President ... (full story)