Sen. John McCain (R-Ariz.) in 2008. (Gerald Herbert/AP)

The leadership themes that have emerged from the obituaries, memoirs and eulogies for Sen. John McCain since his death Saturday won’t surprise most people familiar with the life of the celebrated war hero: the candid and courageous Arizona senator who symbolized so much for so many. The unyielding brawler impatient for the next fight. The maverick politician who bucked the party line. The brave naval aviator who survived years of torture. The straight-talking politician who seemed to captivate the political press.

Yet for those who have not read McCain’s books or followed his remarks about his political career closely, a related aspect to that last characteristic of McCain’s leadership may be less familiar than the others. Over and over again, the journalists who wrote his obituaries and covered his career and the political staffers who worked alongside him spoke of his willingness to speak openly about his mistakes, be candid about where he’d gone wrong, and express regret for what he wished he’d done differently.

While McCain’s “Straight Talk Express” campaign and plain-spoken style is often remembered for the times he countered party dogma or for the unfiltered candidate behind it, there is something more to it than just plain frankness. It was also, many remembered, about how that enabled him to reflect, often critically, upon himself. “No one combined McCain’s unflinching mix of bracing candor, impossibly high standards, and rueful self-recrimination when he (inevitably) failed to live up to the ideals he outlined for himself,” wrote Todd S. Purdum, who covered McCain during the 2006 midterms as he stumped for candidates in the lead-up to his 2008 presidential run, for the Atlantic.

The Washington Post’s obituary for McCain includes his regrets over his involvement in the “Keating Five” scandal, in which McCain and four other senators were accused of trying to get regulators to back off investigations of a savings and loan businessman. "It will be on my tombstone, something that will always be with me, something that will always be in my biography,” he said, “and deservedly so.”

Speaking about his decision to shift from calling the Confederate flag “a symbol of racism and slavery” to saying he could “understand both sides,” he later wrote about his regrets. “I had not been just dishonest. I had been a coward, and I had severed my own interests from my country’s. That was what made the lie unforgivable,” he recalled. “All my heroes, fictional and real, would have been ashamed of me.”

Recent days have produced many such recollections of McCain’s self-reflection and self-criticism. It was his “capacity for brutal self-assessment” about things such as a lack of interest in economics, wrote Sasha Issenberg for Politico, that may have cost him the 2008 election. CNN’s Jake Tapper tweeted Friday that after his cancer diagnosis, McCain said he’d like to be remembered as someone who “served his country and not always right. Made a lot of mistakes. Made a lot of errors, but served his country. And I hope we could add honorably."

A former foreign policy adviser recalled that McCain “emphasized his imperfections. The senator admitted his errors, and he learned from them, and then he went on to make new and different ones." Eliot Cohen, the Johns Hopkins professor and former counselor of the State Department under Condoleezza Rice, wrote that McCain “repeatedly told audiences and readers of his books” that he was a flawed man.

That willingness to self-reflect, to self-criticize, to admit to flaws is, of course, unusual in the American political system, particularly today, as the country is led by a president who hardly ever apologizes or admits a mistake. But it is also considered an essential quality for leadership. Many leaders and researchers have written about its importance — even calling it the “quality that trumps them all” among attributes for leaders. It cultivates trust and transparency. It creates a sense of vulnerability that offers authenticity. Most of all, it helps leaders to learn.

A candid style and maverick record — though he was also criticized for liking the label but not living up to it — may be the leadership attributes most people associate with McCain. But as so many remembered in recent days, that unfiltered voice was not just about being accessible, or willing to stray from his party, but also about being willing to admit his failures in an environment where that remains rare.

“There is no reward in American politics for public displays of self-awareness or self-criticism,” wrote the Atlantic’s editor in chief, Jeffrey Goldberg. "And yet, John McCain understood human nature, and his own nature, enough to state the plausible: that in moments of great testing, it is possible for any human, including the bravest human, to fail.”

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