Trump Says He'll 'Appoint' Gen. James 'Mad Dog' Mattis as Defense Secretary

PHOTO: Retired Marine Corps Gen. James Mattis speaks during the DIRECTV and Operation Gratitude day of service at Caesars Palace, July 23, 2015 in Las Vegas. PlayBryan Steffy/Getty Images
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President-elect Donald Trump announced Thursday night that he will "appoint" retired Marine Gen. James "Mad Dog" Mattis to be his secretary of defense.

"We are going to appoint 'Mad Dog' Mattis as our Secretary of Defense," Trump said in Cincinnati, Ohio. "But we're not announcing it till Monday so don't tell anybody. Mad dog. He's great. He is great."

Mattis retired from the Marine Corps in 2013 after a 41-year career in which built a storied reputation for his leadership of troops in Kuwait during the Persian Gulf War, as well as the wars in Afghanistan in Iraq.

The 66-year-old earned his nicknames 'Mad Dog' and the 'Warrior Monk' for his attention to military tactics and strategy. He is known for his candor and blunt talk, which have at times gotten him into hot water.

Mattis emerged as a frontrunner for defense secretary after Trump met with him at his estate in Bedminster, NJ.

The president-elect soon after tweeted, calling Mattis "very impressive."

In addition to being confirmed by the U.S. Senate, Mattis would also need a special waiver from Congress due a statute that bars members of the armed services from entering government positions intended for civilians until seven years after their retirement.