James Mattis

Several people sometimes mentioned as possible replacements have already come out against pulling U.S. troops out of Syria.

Defense Secretary Jim Mattis resigned Thursday, saying he'll stay until the end of February.

The border mission with no name will continue past Christmas and through the end of January, the DoD announced on Tuesday.

The Secretary of Defense said that Putin's actions have become a catalyst for NATO countries to "rearm and to strengthen."

It just shows that Russia cannot be counted on right now to keep its word," Defense Secretary Jim Mattis said.

Mattis argued that acting to punish Saudi Arabia now could derail the latest effort to convene peace talks on Yemen.

The Air Force announced earlier this month it has expanded BMT from seven-and-a-half weeks to eight-and-a-half weeks.

It's time for a political settlement, Mattis said last Wednesday in a wide-ranging informal session with Pentagon reporters.

U.S. troops will set up observation posts in northern Syria to help prevent partisan infighting.

Mattis and the outgoing SOUTHCOM commander praised the recent decision to send a U.S. Navy hospital ship to aid Venezuela.