Diplo-what???

U.S. Defense Secretary Jim Mattis said on Friday that Syria had dispersed its warplanes in recent days and that it retained chemical weapons, an issue he said would have to be taken up diplomatically.  The United States launched dozens of missiles earlier this month against a Syrian air base in response to a chemical attack that killed 90 people, including 30 children. It says the Syrian government launched the attack from the Shayrat air base.  Reuters