Chamberlin is a rare bird in this city--a lone flier, whom others are compelled to notice. In the past six years she's had about as good a tour as anyone for seeing how the world works. And the journey has changed her.

It's not that the players in Washington can't evolve. They can. But in this partisan era, participants in the great public debates often profit by staying put, safely on the side of one assembled team, even when their hearts may be ready to stray. Wendy--having traveled such a unique and wide-ranging path--is all but impossible for any team to claim. She's free to wander.

Which is what she's doing today, her third day as head of the Middle east Institute. It's an old-guard nongovernmental organization built by the "wise men" of the 1940s--many of them patricians--who guided America through World War II and gave the world the Marshall Plan. She has nothing on her schedule to speak of, but that seems to suit her, giving her time to get her bearings. after what she's been through, it might take a few days.

She left town in July of 2001 to become the U.S. ambassador to Pakistan, a job that seemed manageable, if challenging, after a twenty-six-year career at the State Department that included tours in Laos, Malaysia, and Indonesia. As with every other American, nothing could have prepared her for 9/11. In her case--like a few dozen people in key jobs at that moment--being overwhelmed would have directly threatened national security.

She was there for many of the most important firsts: the first moments of startled clarity, the first phone calls from Washington to Islamabad, the first high-level meetings. On Thursday morning, September 13, she brought the list of eighteen key military demands to President Pervez Musharraf and sat stiffly in his office for forty minutes until he answered the question she'd carried from the president: "Are you with us in this fight?" When he said, "I am, without conditions," she got up and left. That night Powell called Musharraf briefly to run through the eighteen points that officially placed him at war with the radical elements who ran parts of Pakistan--including segments of its military and intelligence services--and with an organization they'd helped create, the Taliban.

And she was in her office in Islamabad on March 17 for the first suicide bombing in Pakistan since the mid-'90s. It killed an embassy staffer and her teenage daughter, along with six Pakistanis. She decided she had to order all nonessential personnel out of the country, which meant that her two daughters--twelve and fourteen--would have to go. as a divorced mother and their main caregiver, she would soon follow.

Not that her new job in Washington--running Asia and the Near East for the United States agency for International development, or USAID--took Wendy far from the fault line; that line seemed to follow her. The job controlled aid and development for a region that included Iraq, which she oversaw before the U.S. invasion and in the nine months following it. She can tell you stories galore about where the $3 billion she allocated ended up, things she did--built 3,500 schools and opened them on time--and things she might have done, which is a long list. When, in early 2004, Rumsfeld consolidated all such efforts under the "unity of command" at the defense department, and took the $3 billion, Chamberlin walked out the door and out of Washington. She was already fifty-four, but there was another job beckoning--something quite different. The UN needed a new Deputy High Commissioner for Refugees. So she packed up her girls, moved to Geneva, and ended up circuit-riding between the planet's worst pockets of human suffering . . . .