Whether about doubling down on Afghanistan, or opposing tariffs on U.S. allies, or confronting Russia, Tillerson was always a kindred spirit.
Though coming from vastly different backgrounds, Mattis with his distinguished four-decade military career, and Tillerson as a globetrotting energy executive, the two were seen as an effective duo and made up two-thirds of the so-called "suicide pact" with Treasury Secretary Steven Mnuchin. The three reportedly have agreed to leave if one of them is fired.
And as a strong believer in diplomacy to resolve conflict, Mattis, a grizzled former Marine commander, made no secret of his close relationship with the America’s top diplomat.
“It starts with me having breakfast every week with Secretary of State Tillerson,” Mattis said in January as he was rolling out the National Defense Strategy. “We talk two, three times a day, sometimes. We settle all of our issues between he and I, and then we walk together into the White House meetings. That way, State and Defense are together.”