Donald Trump announced via social media Sunday that Marine Gen. James Mattis is a contender to serve as secretary of defense in his administration.
"General James 'Mad Dog' Mattis, who is being considered for Secretary of Defense, was very impressive yesterday. A true General's General!" Trump tweeted.
Trump met with Gen. Mattis for about an hour Saturday afternoon at the Trump National Golf Club in Bedminster, New Jersey.
After the meeting, Trump told reporters the general was "a great man, the real deal."
Image: Trump and Pence greet Mattis in Bedminster
U.S. President-elect Donald Trump (L) and Vice President-elect Mike Pence (R) greet retired Marine General James Mattis in Bedminster, New Jersey, U.S., November 19, 2016. REUTERS/Mike Segar/File Photo MIKE SEGAR / Reuters
Mattis who boasts 44 years of service in the Marines, is a retired four-star general who earned accolades for his leadership during the Iraq War, particularly 2004's Battle of Fallujah — largely considered one of the bloodiest clashes of the war.
"Mad Dog" also led a task force in southern Afghanistan in 2001 and a Marine division during the Iraq invasion. He served as commander of NATO's Allied Command Transformation in Norfolk, Virginia before earning a 2010 promotion to run U.S. Central Command — a position that placed him in charge of all American forces stationed in the Middle East.
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Since leaving the military, Mattis has been a loud critic of Obama's Iran nuclear deal and has derided the current administration's lack of desire to pursue military confrontations.
Image: Mattis testifies before the Senate Armed Services Committee hearing on Capitol Hill
General James Mattis testifies before the Senate Armed Services Committee hearing on Capitol Hill in Washington, U.S., July 27, 2010. REUTERS/Yuri Gripas/File Photo YURI GRIPAS / Reuters
But Mattis faces a large speed bump on the road to lead the Pentagon. The former general is currently ineligible to be secretary of defense — per Title 10 of the U.S. Code — as the position needs to be "appointed from civilian life by the president." The law adds that "a person may not be appointed as Secretary of Defense within seven years after relief from active duty as a commissioned officer of a regular component of an armed force."
Mattis retired from the military in 2013.
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If nominated by Trump, however, Congress could provide Mattis a waiver, allowing him to pursue the position.
Congress has only used a waiver once in the history of the country: in 1950. This allowed President Truman to appoint Gen. George Marshall to the position, who served as secretary of defense for a single year.