This is a story that Defense Secretary Jim Mattis would prefer you just skip over.

It’s a portrait of a man walking a tightrope as he navigates a job full of life-and-death decisions working for a president whose style, and sometimes views, sharply contrast with his own.

One year into his tenure as Pentagon chief, the legendary Marine commander, known for his quotable quips and strategic acumen, has adopted a profile lower than any of his predecessors in recent decades.

Asked if Mattis is deliberately keeping his head down to avoid inadvertently provoking his notoriously temperamental boss, one senior Pentagon official said, “Yes, that’s it. I think you’ve nailed it.”

But the official quickly added it’s also simply not in Mattis’ nature to seek the limelight. He abhors manufactured press events, has no desire to be the center of attention, and prefers to work behind the scenes, out of the public eye.

Mattis has conducted only two full-fledged on-camera news conferences in the Pentagon’s commodious briefing room, and the last one was eight months ago in May. He's appeared only once on a Sunday talk show, "Face the Nation," also in May.

When traveling overseas, he does the obligatory joint news conferences with foreign counterparts. He testifies regularly before Congress, but those are essentially command performances.

Left to his own devices, Mattis prefers to engage the Pentagon press corps in impromptu hallway encounters. They're usually on-the-record, but always off-camera, something no previous defense secretary in recent memory has done.

When he does speak to reporters, Mattis is careful never to share any private advice he has given the president, but it’s often clear they are not on the same page.

In August, when Trump tweeted “The U.S. has been talking to North Korea, and paying them extortion money, for 25 years. Talking is not the answer!” a reporter asked Mattis about it at welcoming remarks for the visiting South Korean defense minister outside his third floor office.

Apparently unaware of the president’s morning tweet and caught off guard, Mattis at first joked, “You're testing us, here, you know. We bring you up here to take pictures,” but then said, “No. We're never out of diplomatic solutions.”

The off-the-cuff and entirely unremarkable comment turned into a gotcha moment when Mattis was portrayed as flatly contradicting his boss.

“It was widely misinterpreted,” Mattis told reporters a few days later during one of his unannounced drop-ins with Pentagon correspondents at their C-Ring workspace.

Mattis dismissed the narrative as “a story that some people want to write,” but also acknowledged he needs to chose his words carefully so as not to be seen as disputing the president’s policies.

“I'll do my best to call it like I see it, but right now, if I say six and the president says half a dozen, they're going to say I disagree with him,” he lamented, albeit with a smile on his face.

Trump clearly has an affinity for his defense secretary, who he often calls “general,” even though only a civilian can run the Pentagon. Mattis needed a waiver from Congress because he had not been out of uniform long enough to qualify.

And Mattis' radar-evading, low-key style has saved him from the kind of public dressing down Trump has dished out to Secretary of State Rex Tillerson, or the unfriendly fire directed at national security adviser Lt. Gen. H.R. McMaster from some conservative quarters. The Center for Security Policy, for example, has called for McMaster to be replaced for undermining Trump’s agenda.

Perhaps the best example of Mattis’ invisible hand deftly steering policy is how he and the rest of the national security team slowly brought the president around to the idea that his gut was wrong about giving up on Afghanistan after 16 years of stalemate.

“My original instinct was to pull out, and historically, I like following my instincts,” Trump said when he announced his new Afghanistan policy last summer. But he conceded “many meetings” over “many months” convinced him of the Mattis view that a more aggressive strategy would turn the tide of battle.

More recently, Mattis showed how he follows a wholly different playbook than Trump when it comes to dealing with recalcitrant allies such as Pakistan.

While Trump, in a New Year’s tweet, called out Pakistan for allegedly giving aid and comfort to terrorists and threatened to cut its foreign aid, Mattis, in a visit to Islamabad last month, said nothing provocative in public, and even refused to acknowledge he would prod the Pakistanis to do better.

“That's not the way I deal with issues,” Mattis told reporters traveling with him. “We will work together and we'll find that common ground, if we have the will to. And then, we'll work on how we address the problems where we can work together.”

But while Mattis was anodyne and inoffensive in public, Pentagon sources say in private meetings with Pakistani military leaders, he produced files full of evidence that Pakistan was supporting the Haqqani terror network, and demanded changes.

To be sure, Trump’s penchant for tweeting from the hip doesn’t make Mattis’ job any easier, but it's also not clear that it causes Mattis much trouble.

“I see Secretary Mattis as a cool cucumber who thinks strategically and has enough on his mind without playing all the same Washington gotcha games and reacting to all the Trump tweets the way the rest of the town often does,” said Michael O’Hanlon of the Brookings Institution. “I believe he focuses on big policy issues and decisions, not the daily distractions.”

And aides to Mattis say he also doesn’t want to be one of those distractions. On a recent trip to the U.S. naval base at Guantánamo Bay, Cuba, Mattis took only one reporter and made no announcement ahead of time.

The reason was he wanted to visit the troops, and he didn’t want to be the story.

“As a former military commander, he's been on the receiving end of those VIP visits,” said one Pentagon official, who explained Mattis wanted to avoid having troops pulled off holiday vacation to get ready for the defense secretary’s visit.

“He feels he is serving the country, and particularly the people in the military,” said one longtime friend, who asked not to be identified. “He did not seek the job, and he is doing his best to helm the ship in uncharted waters.”

As for his relationship with Trump, “He respects the Constitution. Trump is legally the president, and Mattis has spent his career defending the Constitution.”

So, will he write a tell-all book once his time as Trump’s Pentagon chief is over?

“Almost certainly not,” said his friend. “Not his style.”

Mattis’ office was offered a chance to comment on this story, but in keeping with Mattis' publicity-adverse style, declined the opportunity.