James Mattis is the incumbent US secretary of defense, who used to be a US Marine Corps general. He was head of US Central Command during the Obama presidency. Mattis is an opponent of military cooperation with Russia.
Defense Secretary James Mattis' cautionary tone on Syria could land him in hot water with Trump, but the president probably can't afford to shake up his Cabinet right now, former CIA officer Philip Giraldi told RT.
US Secretary of Defense James Mattis reiterated that the Pentagon still has no independent evidence to confirm that there was a chemical weapons attack in Syria last week, but said he personally believes there was one.