“Using every skill I had learned during my decades as a Marine, I did as well as I could for as long as I could,” former Defense Secretary Jim Mattis wrote of his time in the Trump administration. | Zach Gibson/Getty Images Politics Mattis warns against divisiveness: 'We all know that we’re better than our current politics'

Former Defense Secretary Jim Mattis, reflecting on his decades-long military career and his recruitment three years ago to serve as President Donald Trump’s Pentagon chief, warned on Wednesday against the “internal divisiveness” and “tribalism” prevalent in American politics — but stopped short of rebuking the sitting commander in chief.

“Unlike in the past, where we were unified and drew in allies, currently our own commons seems to be breaking apart,” Mattis wrote in an essay published in The Wall Street Journal.


“What concerns me most as a military man is not our external adversaries; it is our internal divisiveness,” he continued. “We are dividing into hostile tribes cheering against each other, fueled by emotion and a mutual disdain that jeopardizes our future, instead of rediscovering our common ground and finding solutions.”

The retired Marine Corps general, who exited the administration a year ago over his disagreement with Trump’s order to withdraw U.S. forces from Syria, also implored Americans “to recognize that our democracy is an experiment — and one that can be reversed. We all know that we’re better than our current politics. Tribalism must not be allowed to destroy our experiment.”

Unlike some former White House officials and Cabinet secretaries, Mattis has refrained from directly criticizing the president since he left government, although his resignation letter in December 2018 was widely viewed as an admonishment of the president’s foreign policy posture.

Former Defense Secretary Jim Mattis left the Trump administration over his disagreement with the president's order to withdraw U.S. forces from Syria. | Win McNamee/Getty Images

“Because you have the right to have a secretary of defense whose views are better aligned on these and other subjects, I believe it is right for me to step down from my position,” Mattis wrote to Trump at the time.

In his essay on Wednesday, Mattis alluded to the eventual fissure in his working relationship with Trump and emphasized his support for the United States’ close strategic relationships with global partners.

“Using every skill I had learned during my decades as a Marine, I did as well as I could for as long as I could,” Mattis wrote. “When my concrete solutions and strategic advice, especially keeping faith with our allies, no longer resonated, it was time to resign, despite the limitless joy I felt serving alongside our troops in defense of our Constitution.”

Mattis earlier this month rejoined the board of directors of General Dynamics. He first became a member of the government contractor’s board in August 2013 after retiring from the Marine Corps, but was required to resign , divest his stock and recuse himself from all matters involving the company for one year after he was confirmed as Defense secretary in January 2017.