Former Defense Secretary Jim Mattis has advice for military officers getting ready to lead troops in combat: Listen to your noncommissioned officers, be physically tough, and know your troops. Do that, and they’ll make you proud on the battlefield.

Mattis shared that sage advice during a recent talk presented by the OSS Society in response to a question he hears often from young officers just starting out in their careers. Mattis, 71, served in the Marine Corps for 44 years at every level of command until he retired as the head of U.S. Central Command in 2013. The retired four-star general later served as President Donald Trump’s first and longest-serving defense secretary until resigning in protest in 2019.

“The first point is, listen to your noncommissioned officers or your chief petty officers,” Mattis said. “They don’t expect you to do everything they recommend. But they do expect to be heard.”

You’ll need to be a good listener, Mattis advised, which means keeping an open mind and having a willingness to be persuaded. Because the enlisted troops have far more experience, or, in Mattis’ words, “they were getting a master’s degree” in soldiering while you were still in high school.

“Listen to them,” Mattis said. 

And, while it may be overused — and ignored by some — leading by example holds true, especially when it comes to combat where physical toughness is a matter of leadership, Mattis said.

“There is no way that you can walk in there and not be physically at the top of your game and expect that physical rambunctious young troops are going to respect you,” said Mattis, who commissioned as an infantry officer in 1972.

“They really don’t care that you read [Carl] von Clausewitz or some other dead German,” he said. “They’re going to assume you know how to call artillery support, but don’t try to wow them with your knowledge if you can’t keep up with them on any run.”

Officers should be doing just as many pullups as their young troops, Mattis said.

“They’ve got to know that the toughest coach in the ballgame is theirs,” he said. “And he or she can stand the strain.”

Mattis cautioned that leaders should not give up “one ounce” of authority, but they should come as close to the necessary line of knowing their troops without getting too personal. Because they won’t let you down if they know that you sincerely care about them.

“Know not just their name but what are their hopes? What are their goals?” Mattis said. Do they want to stay in the armed forces or get out? If it’s the latter, what’s the plan for college, and where are they going to live?

“And the more you know about the troops, the more they know you care about them as individuals, and the less apt they are to let you down when they’re out of your sight,” Mattis said. “They just know that the bond is too close.”

So know your troops well, listen to your NCOs, be physically tough, and know your job. And it doesn’t hurt to be handy with small arms, too. 

“And I think that’s probably about enough wisdom from an old general,” Mattis said.

You can watch the full 90-minute interview with Mattis here.

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