Defense Secretary Jim Mattis (Army photo)

Former Marine General and Defense Secretary James Mattis has been reelected to the Board of Directors of General Dynamics [GD], where he previously served on the board between August 2013 and January 2017.

Mattis, 68, resigned last December as President Trump’s Defense Secretary due to a number of differences with the president that included treatment of U.S. allies and the need to be “clear-eyed about both malign actors and strategic competitors.”

He is currently the Davies Family Distinguished Fellow at the Hoover Institution at Stanford Univ.

Mattis’ appointment to board was effective on Wednesday.

“Jim is a thoughtful, deliberate and principled leader with a proven track record of selfless service to our nation,” GD Chairman and CEO Phebe Novakovic said in a statement. “We are honored to have him on our board.”

Mattis retired from the Marines in 2013 after a 43-year career, with his service including command of U.S. Central Command and U.S. Joint Forces Command.