Gen. James Mattis is held in the highest regard by other warfighters
Credit: DON EMMERT/AFP/Getty

Gen. James ‘Mad Dog’ Mattis, the iconic former Marine Corps general President-elect Donald Trump picked to run the Pentagon, faces his Senate confirmation hearing on Thursday.

Senators are expected to ask Mattis hard-hitting questions on topics including civilian control of the military and future U.S. policy toward Russia and Iran, Reuters reports.

When announcing Mattis as his pick for defense secretary last month, Trump praised the retired four-star general as the “closest thing to General Patton that we have.”

As he fields questions from senators on Thursday, here are six things to know about Mattis, who retired from the military in 2013 after serving his final duty assignment as chief of the military’s U.S. Central Command (CENTCOM).

1. He is held in the highest regard by other warfighters

“He is one of the finest military officers in American history,” says historian and former Army Infantry officer James Lechner, who served under Mattis in combat in Iraq. “I put him right up there with Patton and Robert E. Lee.”

The warriors admire Mattis for a range of qualities.

“His positive energy emanates to the entire force,” says Frank Grippe, himself a legendary soldier who served as Command Sergeant Major of CENTCOM under Mattis. “He is a scholar, a gentleman, and among the most gritty, courageous, at-home-in-the-dirt warriors our great nation ever produced.”

Mattis understands how to balance the approach to war, insiders say.

“Not only is he as tough and as dynamic a warrior as anyone who commanded U.S. troops, but he can turn right around in the same breath and be one of the most prescient diplomats I’ve ever encountered,” Lechner says. “He is a master of counterinsurgency. He is one of the few people who know how to fight a counterinsurgency at the tactical and strategic level.”

“He is a self-actualized package of mind, body and spirit,” Grippe says.

2. He is devoted to warfighters in a personal way

Mattis is known for putting the troops first, and for caring deeply about their welfare.

The former commandant of the Marine Corps, General Charles Krulak, has been quoted as saying he once was shocked to find Mattis pulling guard duty on Christmas Day at Marine Base Quantico in Virginia. The officer who originally was scheduled for guard duty that day had a family, and Mattis decided to take the man’s place so that the young Marine could spend Christmas at home.

The devotion hasn’t lessened over time.

Several weeks ago, this reporter was at an Irish pub in Tampa with some wounded warriors, Grippe, and Jill Kelley, when the group decided to call Mattis. During the call, Mattis spoke to Joel Tavera, who was blinded and seriously wounded in 2008 in Iraq. While on the phone, Mattis repeatedly asked Tavera how he was doing, listened at length, and expressed sincere gratitude for the Army vet’s service.

3. He is a bookworm and an intellectual

Mattis owns an extensive personal library that is said to include some 7,000 volumes.

“He is a prolific reader,” Lechner says. “He reads constantly.”

The scuttlebutt among other warfighters is that Mattis loves reading so much that he brought his entire library with him in packing crates on each deployment. He once engaged in an email exchange where he extolled the virtues of reading.

Mattis practiced what he prescribed. He was said to have been spotted often in quiet moments after hours, reading contentedly.

One particularly dog-eared tract was Meditations by Roman Emperor Marcus Aurelius.

Mattis’ reputation as an intellectual has spread to the civilian world. On Monday, Newt Gingrich told reporters Mattis is one of the smartest people in the military.

When he sets down his books and his weapons, Mattis also seems to enjoy talking about military history and operations.

Last summer, this reporter called Mattis on his cell phone to ask about combat operations in Kunar Province, Afghanistan in 2011. After first saying he did not have time to talk, Mattis spent some 30 minutes discussing Afghanistan war operations, policy, and combat theory in general, offering keen insights and observations.

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4. He is known for his “Mattisisms”

Mattis has the ability to craft memorable phrases that can wind up as popular memes. Some of his best known “Mattisisms” are as follows.

“I come in peace. I didn’t bring artillery. But I’m pleading with you, with tears in my eyes: If you f— with me, I’ll kill you all.”

“Be polite, be professional, but have a plan to kill everybody you meet.”

“I’m going to plead with you, do not cross us. Because if you do, the survivors will write about what we do here for 10,000 years.”

5. He has been given colorful nicknames

Unlike other secretaries of defense, who have gone by “Sir,” or “Mister Secretary,” Trump’s pick for the position also answers to three nicknames.

“Mad Dog” comes from his demeanor in combat.

“Chaos” was his Marine Corps callsign. Mattis reportedly has said it is an acronym for “Colonel Has An Outstanding Solution.” But the Marines reportedly believe the callsign means … chaos.

“The Warrior Monk” because he is a bachelor who has devoted his life to studying and waging war.

6. He has opposed putting women in direct combat

Women should not be sent into the “atavistic primate world” of close combat, Mattis has been quoted as saying. The website quoted speeches by Mattis to the Marines’ Memorial Club in San Francisco, where he reported said, “The idea of putting women in there is not setting them up for success.”

Physical requirement such as pushups and pullups were “not the point,” Mattis reportedly said, directing his comments to the nature of what he termed “intimate killing.”

Only someone “who never crossed the line of departure into close encounters fighting … would ever even promote such an idea” of sending women into close combat, Mattis reportedly said.