When she appeared at Columbia University in New York last week, Samantha Power looked pale and drawn. Wrapping her red mane around her like a protective shawl, she did all she could to avoid the phalanx of reporters who had turned out to listen to her speak.
The reason for her reticence was simple: she knew that a couple of hours later President Obama would address the nation and the world on the subject of the air strikes against Colonel Gaddafi in Libya, and she has learned from bitter experience -- she had to leave his primary campaign after calling Hillary Clinton a "monster" -- that she cannot allow herself to become the story.
Better to leave them with a good quote -- that failure to defend the no-fly zone would have been "extremely chilling, deadly and indeed a stain on our collective conscience" -- and get out of there.
Still, when Obama later used almost exactly the same language in his speech and Hillary Clinton followed up by repeating that she would not seek another term as Secretary of State, the talk around Washington inevitably turned to Power possibly taking over the role should Obama fend off his Republican challenger next year.
The 40-year-old Dublin woman has long had the President's ear, and several leading conservative commentators -- including Glenn Beck of Fox News -- have already called her a shoo-in for the job when it arises.
A laudatory profile in The New York Times also talked up her credentials last week and pointed out that her husband, constitutional law scholar Cass Sunstein, already runs the White House's Office of Information and Regulatory Affairs. Should his wife be appointed to the Secretary of State post, she would become the most powerful Irish person in the world.
Not everyone would be pleased if this happens, and assuredly Power has her critics: US media reports have depicted her as the author of the attacks on Libya -- an unpopular conflict for Americans, who see their country already mired in two unwinnable wars. An article on the generally liberal Salon.com phrased it somewhat uncouthly, saying Obama had been "pussywhipped" into war by a coalition of women, including Power and Clinton.
The Irish academic (she is also a professor at Harvard) and presidential adviser has reconciled herself with the current Secretary of State, but the truce hangs on Power not stepping on Clinton's toes. And that involves staying as much as possible out of the limelight.
Still, it would be unfortunate if such a high-profile appointment caused Power to suppress her natural extroversion. There has always been a touch of glamour and celebrity to go with the Pulitzer Prize and Ivy League degrees (she has two).
Even as she grew closer to Obama she posed in an evening gown for Men's Vogue, and her writing on genocide brought her into contact with George Clooney, who has campaigned for Darfur. She still calls him a friend.
In person she is an imposing presence; the phrase "genocide chic" has been used to describe her. You can see why they once got Julianne Moore to play her on Broadway, even if Professor Power herself wasn't thrilled with the performance.
She's been in America for three decades now. Before that her parents lived in Ballsbridge in Dublin. Her father, from Athlone, was a dentist and her Cork-born mother was training to be a doctor. The marriage was on the rocks and her mother went for further study to America, taking Samantha and her five-year-old brother with her.
The brogue was one of the first things to go -- carefully removed through practice in front of a mirror in Pittsburgh -- but she would regret trying to fit in.
Her father died in 1983 and a peripatetic childhood took Samantha to Kuwait City (for further training for her by-then highly qualified mother), and then from Pittsburgh on to Atlanta where she spent her teenage years.
"I can clearly remember my first day of American public school in Pittsburgh. I had to wear my Mount Anville school uniform in front of all those kids because my mom didn't have any money for new clothes," she told the Sunday Independent in an interview two years ago. "It was totally humiliating for life. The shirt, black leather shoes and pleated skirt. Years of therapy later, I'm still not over it.
"If you really want to know how I got interested in war zones, you'd have to go back to that first day of school in the Mount Anville uniform."
As a teenager she won a place at Yale University, but rather than diving straight into academia she decided to work as a journalist in the Balkans. She covered the Yugoslav wars for The Boston Globe, the Economist and the New Republic.
"I saw those images of the emaciated men standing behind the barbed wire and it was a siren and a summons," she said. "It was naive to think that there could be any benefit in one more voice to the chorus calling for action, but that's how I thought. I didn't feel like I was taking a mortal risk, but as soon as I got there I wanted to be in Sarajevo, where the action was. Before I became I journalist I had no idea I had this ailment."
Her way of getting this out of her system was to write A Problem from Hell: America and the Age of Genocide. The book discussed America's responses to genocides in the 20th Century, from the Armenian genocide to the ethnic cleansing of the Kosovo war, and it won Power the Pulitzer Prize for Non-Fiction in 2003.
Barack Obama read it over Christmas 2004 and contacted her with words of praise. He recruited her to his 2008 Democratic primary campaign, but she was forced out after a Scottish newspaper shafted her by printing an off- the-record remark about Hillary Clinton. She remained an influence on the president, however, and after the bad blood of the bitterly fought primary was dealt with by appointing Clinton Secretary of State, the way was open for Power's return.
And now, with curious symmetry, the Irishwoman might be about to take Hillary Clinton's job. After the president gave his speech last week, the White House press office was careful to say that Power's remarks had echoed Obama and not the other way around. If the rumours in Washington are true, there may soon be no need for such pretence.