-shooter by those who have worked with him

The retired four-star Marine Corps General has been called a 'warrior monk' and a salty

Retired Marine Corps General James 'Mad Dog' Mattis has been declared one of president-elect Donald Trump's top choices to fill the role of Secretary of Defense.

Keeping in form with Trump's already-filled cabinet picks, Mattis is a controversial figure who will need a congressional waiver in order to server, should the the president-elect select him.

The four-star Marine Corps general, who once said 'it’s fun to shoot some people', according to the Daily Beast, has only been retired for four years. But in order to obtain the position, Secretaries of Defense must be out of the Military for seven.

Arizona Senator and Senate Armed Services Chairman John McCain said that Congress has waived this requirement in the past and that it shouldn't hinder Trump's choice.

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Retired Marine Corps General James 'Mad Dog' Mattis (center) has been declared one of president-elect Donald Trump's top choices to fill the role of Secretary of Defense

The retired general and Trump met on Saturday in what Trump said was a great meeting and called Mattis a 'great man'

A team of lawyers is reportedly working on Capitol Hill to figure out how to make the waiver work for Mattis.

The retired general and Trump met on Saturday in what Trump said was a great meeting and called Mattis a 'great man'.

As Mattis left his meeting with Trump, they shook hands and when asked about how the meeting went, Trump said: 'All I can say is he is the real deal. The real deal.'

In a follow question about whether Trump would choose Mattis for Secretary of Defense, he said: 'We'll see, we'll see.'

Trump added of Mattis that 'he's just a brilliant, wonderful man. What a career. We are going to see what happens but he is the real deal.'

Mattis led Central Command from 2010 to 2013 before retiring. He managed conflicts in the Middle East, North Africa and Central Asia during that time.

Mattis led Central Command from 2010 to 2013 before retiring. He managed conflicts in the Middle East, North Africa and Central Asia during that time

He often butted heads with the Obama administrations, which he saw as weak and too hasty to remove troops from Afghanistan.

Mattis has made many comments criticizing the Obama administration from innocuous details to things as dire as failing to prepare to battle an expansionist Iran, according to the Daily Beast.

'The international order… is not self sustaining. It demands tending by an America that leads wisely, standing unapologetically… in defense of our values,' Mattis said.

His fellow Marines have lauded him as a 'warrior monk' and at one point he was poised to run against Trump as the nominee for president.

Those who have worked with him say he's a straight shooter known for his salty language, often referred to as 'Mattisisms'.

One pearl of wisdom includes: 'Be polite, be professional, but have a plan to kill everybody you meet.'

In 2005 he made an infamous remark about killing people in Afghanistan: 'You go into Afghanistan, you got guys who slap around women for five years because they didn’t wear a veil. You know guys like that ain’t got no manhood left anyway, so it’s a hell of a lot of fun to shoot them.'

His fellow Marines have lauded him as a 'warrior monk' and say he's a straight shooter known for his salty language, often referred to as 'Mattisisms'

If appointed, Mattis would add to Trump's cabinet of 'national security super-hawks' and cause a more aggressive defense of the U.S., the Daily Beast reported.

'I’m a great admirer of Gen. Mattis. I think one of the reasons why it would be good to have him is that he has recent combat experience in both theaters (Iraq and Afghanistan). So he really understands complex situations on the ground,' McCain told The Daily Beast.

McCain's Senate Armed Services will have to confirm more than 50 position related to defense in Trump's administration.

'As dire a situation as it is, I think he is by far the most qualified individual,' McCain said.

One pearl of wisdom includes: 'Be polite, be professional, but have a plan to kill everybody you meet'

Illinois Republican Rep. Adam Kinzinger also told the Daily Beast he would approve of Mattis in the position.

'He’s a man of character and integrity. He’s given his life to his country,' John Noonan told the Daily Beast.