I have never met an unassuming four-star general. If such creatures do exist, it's a safe bet that they're lousy at the job. This is worth keeping in mind when puzzling over the scandals of Gen. David Petraeus and, now it seems, his successor in Afghanistan, Gen. John Allen.
Consider what a general does, especially in wartime: He sends his soldiers into battle, knowing that some of them will die as a result of his decisions.
That doesn't necessarily make generals bloodthirsty or immoral (I've met very few who fit that description), but it does require them to be supremely self-confident, even arrogant. When issuing orders, they can't display the slightest sign of ambivalence or hesitation. If they did, they would soon lose confidence among the ranks, and the army they lead would fall apart.
Many leaders — not just in the military, but in politics, medicine, the corporate world, all realms of life — have a talent for compartmentalization. Still, there are limits to how far the human psyche can be stretched. It should be no surprise that, sometimes, when people assume such a lofty helm and such extreme levers of power, the sense of self-supremacy that goes with the job can extend to other realms of life.
This is why the U.S. military has such a harsh code of justice, why, for instance, adultery is a firing offense. It isn't just that the guardians of the code are prudes; it's that they know what power can do to someone — and thus they grasp the need to impose the temper of discipline. But codes are not perfect; human foibles occasionally slip through.
News of Petraeus' affair sent shock waves across the nation not just because he's so famous but also because he seemed like such a straight arrow. That was no accident; Petraeus spent years deliberately cultivating that myth.
As I write in my forthcoming book, The Insurgents: David Petraeus and the Plot to Change the American Way of War, he learned the art from two key mentors in his life, both of them generals: John Galvin and Marcel "Bruno" Bigeard. Galvin, a real hero during Vietnam (mainly for his refusal to falsify body counts), hired Petraeus as an assistant in Latin America and Europe. Bigeard, whom Petraeus first met through correspondence, was the French army's most celebrated general (for his resistance at Dien Bien Phu, then his command in the battle of Algiers).
Both men taught Petraeus that a great leader must weave a myth about himself — both to enhance the loyalty of his cadres and to build popular support for his mission. Petraeus learned the lesson well and applied it with skill and vigor.
Petraeus was a genuinely talented general: intellectually agile, strategically minded and tactically bold. But the myth-making enshrined him, in the eyes of many, as an icon. It's hard to imagine that he remained entirely immune to the adoration.
It's also worth noting that some of his greatest achievements during the Iraq war were the result of going a bit rogue. Early in the occupation, he brought order to the northern city of Mosul by applying principles of counterinsurgency theory — creating a new political system, vetting candidates, providing economic services, opening the border to Syria — entirely on his own initiative.
The bold gambles of generalship may have instilled a growing sense that he could make his own rules, that he could get away with almost anything — even something that no one thought he would ever be tempted to try.
Fred Kaplan is Slate's "War Stories" columnist. © 2012 Slate