When Barack Obama arrived in Washington almost five years ago, the universal assumption was that the young president—who had, after all, won office by exploiting every connective tool of the national social and electoral network—would run his White House in sharp contrast to the bunkered, hunkered-down George W. Bush.

Like so much conventional wisdom, that impression has proved dead wrong. In fact, Obama’s resolute solitude—his isolation and alienation from the other players and power centers of Washington, be they rivals or friends—has emerged as the defining trait of his time in office. He may be the biggest presidential paradox since Thomas Jefferson, the slaveholder who wrote the Declaration of Independence: a community organizer who works alone.

In early 2011, when the president’s most trusted political adviser, David Axelrod, left the White House to return to Chicago to run his re-election campaign, Obama made a surprise appearance at Axelrod’s going-away party in a grand apartment off Dupont Circle on a wintry Saturday night. Clad casually in a black jacket, he spoke warmly, even emotionally, of the aide who had done so much to elect him. Then he made his way quickly around a living room full of Cabinet members, other aides, and off-duty reporters, grasping each proffered hand with a single, relentless, repeated greeting: “Gotta go.”

Self-containment is not simply Obama’s political default mode. Self-possession is the core of his being, and a central part of the secret of his success. It is Obama’s unwavering discipline to keep his cool when others are losing theirs, and it seems likely that no black man who behaved otherwise could ever have won the presidency.

But this quality, perhaps Obama’s greatest strength in gaining office, is his greatest weakness in conducting it. And as he ends the first year of his second term, that weakness seems to dog him—and to matter—more and more. At a time when the abrasions of office leave any president most in need of friends, Obama is the capital’s Lonely Guy.

Obama’s self-evident isolation has another effect: It tends to insulate him from engagement in the management of his own administration. The latest round of “what did the president know and when did he know it” on the disastrous rollout of Obamacare and the tapping of German chancellor Angela Merkel’s cell phone raised troubling questions: Were Obama’s aides too afraid to tell him? Was he too detached to ask? Or both? At the least, such glaring failures cast fresh doubt on Obama’s invariable assurance to those around him in times of trouble: “I got this.”

It is impossible to know whether Obama’s go-it-alone approach is instinctual or learned, but he comes by it honestly—and painfully. From a far earlier age and to a far greater degree than is generally understood, Obama has always been alone. He was abandoned not only by his black African father, whom he later met just once at age 10, but also by his white American mother, who left him as a teenager with her parents in Hawaii to pursue graduate fieldwork in anthropology in Indonesia. At an age when most adolescents are grappling with how to break away from their families, Obama’s had crumbled away from him.

“Away from my mother, away from my grandparents, I was engaged in a fitful interior struggle,” he would write in Dreams from My Father. “I was trying to raise myself to be a black man in America, and beyond the given of my appearance, no one around me seemed to know what that meant.”

Give Obama credit for figuring that out, and for rising beyond even the wildest imaginings of his self-reliant youth. If he had chosen to be a novelist or neurosurgeon, an airline pilot or an atomic engineer, the very qualities of self-sufficiency that even some of his strongest supporters find so frustrating would be an unalloyed asset. But in a politician—above all, in a president—such qualities are confounding and, at times, crippling.