Former four stars who have served with retired Army Gen. Lloyd J. Austin III often use similar words to describe him: “quiet,” “low-key,” “introverted.” Those qualities worked for Austin as a senior military commander. They may not serve him well if he becomes secretary of defense.

The news that President-elect Joe Biden plans to name Austin as his Pentagon chief surprised even some of his biggest supporters within the military. They describe Austin as a strong battlefield commander, but as someone who has endeavored to stay out of the spotlight. Such reticence won’t be an option for a defense secretary.

Austin would be a trailblazer as the nation’s first Black defense secretary, and his reserved military bearing would be reassuring to many, at home and abroad. Still, running the Pentagon is one of the world’s hardest management jobs. It requires communications skills hard to learn on the fly.

The appointment fits the collegiality typical of the Biden governing style. Austin is a team player, without the flair or elbows-out assertiveness of some past Pentagon chiefs. He worked well with Biden’s inner circle when they served together under then-President Barack Obama. He wasn’t a vocal enthusiast for keeping troops in Iraq in 2011 or for intervening early against the Islamic State in 2014. Those qualities apparently suit Biden, who was more cautious about using force than many of his Obama-era colleagues.

Jen Psaki, Biden’s press secretary, explained in an interview: “Biden knows him (Austin), he has a comfort level with him. He likes the fact that Austin knows his way around the department. … The historic nature of this pick is not lost on him.”

She said Austin’s “calm” was “appealing,” along with his “ability to manage under pressure.”

But Austin will face two potential hurdles, in addition to the challenge of working with the media. First, many members of Congress want to restore strong civilian control at a Pentagon. As a former commander, Austin would need a special waiver to serve, and though Congress will probably grant it, some will be uneasy. Second, he lacks experience in the Pentagon’s paramount challenge of reinventing weapons and strategy to counter a rising, high-tech China.

One retired Army four star who worked closely with Austin summarizes his guarded approach to public communications this way: “It’s better not to say anything. You don’t make problems for yourself that way. The less said, the better.”

Retired Adm. Mike Mullen, the former chairman of the joint chiefs, said he advised Austin recently that civilian leadership is “much more public” and that he will need to embrace a more open communications approach than the military’s culture typically espouses.

After graduating from West Point in 1975, Austin began a steady rise as an infantry officer. He displayed his tactical skill and bravery in the 2003 invasion of Iraq as an assistant commander in the Third Infantry Division in its race to Baghdad. He was aggressive and “imperturbable” under fire, a colleague said.

Austin rose to become the three-star deputy commander in Baghdad under Gen. David Petraeus during the later years of the troop surge, 2008 and 2009. He impressed colleagues by quickly moving to Basra and creating a tactical command post to direct operations alongside Iraqi troops fighting Iranian-backed militias.

“It was typical Lloyd – very calm, ‘Here’s what I want to do,’ and then doing it,” a fellow commander said.

He wasn’t a celebrity commander with a big public persona. But on the flip side, he wasn’t aggressive in pushing a strategic vision to counter new threats.

Austin was Centcom commander during the Islamic State’s explosive rise, but he didn’t press to intervene early against the terrorist group, former colleagues said. At Centcom, he had succeeded Gen. Jim Mattis, seen by the Obama team as an overly aggressive commander. Austin, by contrast, worked closely with the Obama White House, sometimes to the chagrin of his Pentagon superiors.

Austin’s wariness of the media became a liability after the U.S. intervened in Iraq and Syria against the Islamic State. He kept a low profile and avoided taking reporters into the war zone, which meant the public lacked his commander’s-eye view of the conflict. His successor, Gen. Joseph Votel, immediately reversed that media-shy approach.

Here’s what this choice suggests about Biden and the military: Biden was a skeptic of the United States’ deepening involvement in the Middle East during the Obama years. This reticence may explain the Austin nomination. Sometimes it takes a retired general to say no to other generals, and that may be just what Biden wants.

– Contact David Ignatius on Twitter @IgnatiusPost.