James Mattis’ ascension from a battle-tested Marine general to President Donald Trump’s widely praised and supported secretary of defense enforces his reputation as a “warrior monk” and illustrates his strategic mind. Since 2010, Mattis has gone from being a deputy unified combatant commander with a cult following among Marines but little public profile, to running U.S. Central Command in the Obama administration during a key time, to being unceremoniously ousted from that role, to resisting calls to launch an independent bid for the White House in the 2016 election, and now, to being one of the most influential and consequential defense secretaries in American history.

It’s been a whirlwind decade for the cerebral, combat-tested Marine. In being confirmed as secretary of defense, Mattis required a congressional waiver because it had been such a short period of time since he retired from the military. Such a waiver had only ever been granted once before — to former Army Gen. George Marshall, one of the United States’ most iconic generals and statesmen.

And now, Mattis has been chosen asone of the Time 100, Time Magazine’s list of the world’s most influential people in the world. Bob Gates, a longtime statesman and public servant to our national defense, who served as secretary of defense in both George W. Bush and Barack Obama’s cabinets, wrote the citation for the magazine.

AP Photo by Matt Dunham

How Mattis Made His Comeback

Gen. James Mattis, the head of U.S. Central Command, takes questions after delivering a lecture to the London think tank Policy Exchange in London, Tuesday, Feb. 1, 2011.

“Mattis shares Marshall’s deep knowledge of history, his strategic vision, his appreciation of both America’s national interests and its values, his tough-mindedness about policies and people, and his integrity,” Gates wrote. “Like Marshall, Mattis is also unafraid to speak truth to power.”

But we didn’t need Time Magazine to understand Mattis’ influence and power. Through the opening months of the Trump administration, he’s gained increased autonomy of and influence over key military decisions.The Daily Beast and multiple other outlets reported last month on a shift in executing military operations that grants generals in Mattis’ Defense Department who are outside of designated war zones more authority in launching kinetic military operations.

“President Donald Trump has signaled that he wants his defense secretary, retired Marine Gen. Jim Mattis, to have a freer hand to launch time-sensitive missions quickly,” that report said.

Mattis’ key role as defense secretary comes in a time of global political tumult and instability, and perhaps the steady hand with which he’s handled the past seven years is what has prepared him so well for that role.

Mattis picked up his fourth star and made international headlines in 2010, after the general in charge of the war in Afghanistan, now-retired Army Gen. Stanley McChrystal participated in a scathing Rolling Stone cover story dissing the Obama administration. Obama, in a tough position from the report, fired McChrystal, put then-Army Gen. David Petraeus in charge in Afghanistan, which vacated Petraeus’ post as head of U.S. Central Command. Obama tapped Mattis, who was deputy commander at U.S. Central Command, to be promoted and fill the post. It was Gates who recommended Mattis to Obama for that role.

But by the end of his term running CENTCOM, Mattis’ relationship with the Obama administration, most notably National Security Advisor Tom Donilon, had reportedly soured. According to a January 2013report in Foreign Policy from Pulitzer Prize-winning war journalist Tom Ricks, Mattis only learned that he was being ousted from his post at U.S. Central Command after an aide “passed him a note telling him that the Pentagon had announced his replacement as head of Central Command. It was news to him,” Ricks wrote, “he hadn’t received a phone call or a heads-up from anyone at the Pentagon or the White House.”

The change came, accordinganother piece from Ricks, in part as a result of “National Security Advisor Tom Donilon” being “irked by Mattis’s insistence on being heard.”

Mattis was reportedly more hawkish than the rest of the Obama administration on Iran (hehas called the three greatest threats to the United States: “Iran, Iran, Iran”). Ricks wrote that firing Mattis was a “larger part of an attempt by Donilon to centralize foreign policy making in his office.” The departments of Defense and State were to only be “implementers,” Ricks wrote.

And so Mattis, a Marine general with more than 40 years of service, retired relatively unceremoniously. He took teaching positions at Stanford and Dartmouth, and he participated in discussions on national security and civil service. It was a relatively low profile for Mattis the warrior monk — until 2016, when a brash real estate mogul named Trump hijacked the Republican party en route to an unlikely bid for the presidency. This time last year, Mattis was courted by scared establishment Republicans to launch an independent bid for the White House.

“[Mattis is] a man of character and integrity. He’s given his life to his country. How do you ask someone like that to leap headfirst into this toxic mud puddle of a race? It’s damn hard,” John Noonan, a former advisor for Jeb Bush’s presidential campaign, and a proponent of the effort to draft Mattis,told the Daily Beast’s Tim Mak. “But Trump is a fascist lunatic and Hillary has one foot in a jail cell. That means the lunatic can win. I’d be first in line to plead with the general to come save America.”

DOD photo by Army Sgt. Amber I. Smith

How Mattis Made His Comeback

Defense Secretary Jim Mattis renders honors during an enhanced honor cordon for Spain’s Minister of Defence María Dolores de Cospedal at the Pentagon in Washington, D.C., March 23, 2017.

But Mattis rejected the campaign, and waited to see how things would play out. That’s been the key ingredient of Mattis’ rollercoaster decade: strategic patience. He stayed quiet and behind the scenes during the 2016 election, then quietly accepted the role of secretary of defense. His stellar reputation crafted over his long career allowed him not only to earn his congressional confirmation during a political contentious period, but to earn a waiver that hadn’t been issued in 70 years.

No matter your politics, it is dizzying to contemplate the implications of Trump’s presidency on our geo-political future. What is known, however, is that Mattis has proven himself to be one of his generation’s top strategic thinkers. And what seems increasingly likely is that Mattis will play an outsized and decisive role in what comes next.