SITTING down for a Thanksgiving chat with Barbara Walters, the queen of American television interviewers, Michelle Obama talked last week about her lipstick, her children, Santa Claus, cooking and scooping dog poop from the White House lawn.

She didn’t say a word about the economic crisis, America at war, healthcare, poverty or any of the other issues she had addressed with passion and flair as her husband’s supporter and surrogate during a year of presidential campaigning.

It was a curiously muted performance by Barack Obama’s high-powered lawyer wife, and it helped to fuel an ominous debate about the role of America’s next first lady as she adjusts to a new life as the country’s most scrutinised mother.

To the chagrin of Democratic feminists who had hoped she would become the first presidential spouse to manage an independent career at the White House, Michelle has declared herself “mom-in-chief” and apparently turned her back on the $300,000 (£195,000) salary she earned as a hospital administrator.

As her husband grapples with financial meltdown, Obama has unwittingly been plunged into a renewed outbreak of the so-called “mommy wars”, between stay-at-home mothers and professional women, who both look to Washington for inspiration and example in the unresolved conflict between family and career.

A week before Barack Obama’s election triumph, Michelle took over her husband’s campaign while he slipped back to Hawaii to visit his dying grandmother. At a string of solo meetings in Ohio, she revealed herself to be a powerful public speaker who had managed to shed her initially abrasive image as an outspoken radical who didn’t much like her fellow Americans.

Yet since she appeared with her two young daughters at Obama’s side at their victory celebrations in Chicago, Michelle appears to have abandoned political activism, sparking a flood of media and internet discussion about the so-called “momification” of a previously formidable campaigner.

A widely read column by Rebecca Traister at Salon.com noted that “the majority of the [media] coverage of Michelle Obama . . . since her husband was elected has centred on her clothes”.

Several feminists have complained that despite her degrees from Princeton and Harvard, not to mention her extensive professional experience, she is now being talked about exclusively in “safe” family terms - as the mother of Sasha, 7, and Malia, 10, who will become the youngest children to live at the White House in decades; and also as a female fashion-plate.

“When the needs of our families collide with the demands of our jobs, it is usually the woman’s career that yields,” complained Ruth Marcus, a syndicated columnist. Traister blames a “Hillary Clinton hang-over” for the seemingly potent national desire for traditional family life at the White House. Others noted that Laura Bush, a former librarian who rarely expressed any political views, became one of America’s most popular first ladies despite her husband’s failures.

Michelle has said she sees no contradiction in devoting herself to her children at a critical moment in their lives. When they move from Washington to Chicago, the girls will have to adjust not only to a new private school and new friends, but to the constant presence of bodyguards. It may be no coincidence that the last two children to grow up in the White House - Amy Carter and Chelsea Clinton - turned into extremely private adults who have shunned most media contact.

“I have never been the kind of person who has defined myself by a career or a job,” Michelle told Walters. “People used to ask me that during the course of the campaign - ‘Is it hard for you to have stepped off the track and devoted your life to his dream?’ ” She went on: “But the truth is that I believe in [my husband] as our president, and his vision for the country. And if that meant stepping away from my particular job . . . that’s a small sacrifice to make.”

Michelle depicted herself as a hands-on mother who intends to make sure that Sasha and Malia make their own beds and pick up their new puppy’s mess. Yet several Washington insiders doubt that Michelle will steer clear of politics for ever. “She doesn't seem the type to play Jackie Kennedy for long,” said one Democratic strategist, referring to the popular Washington view that the “Camelot” age of Kennedy glamour is about to be replaced by “Bamalot”.

The president-elect recently said of his wife that he expected her to “design her own role. I think she’s going to set her own path. But she’s serious when she talks about being a mom”.

Michelle noted that she had already been juggling children and career for the past 10 years. “The primary focus for the first year [in the White House] will be making sure that the kids make it through the transition,” she said. “But there are many issues I care about.”

As her husband continues to make history with the help of a long list of powerful women - from Hillary Clinton, expected to become his new secretary of state, to Valerie Jarrett, his senior adviser and Penny Pritzker, the billionaire Chicago businesswoman who has been one of his most valuable fundraisers - it seems only a matter of time before Michelle emerges as more than a stay-at-home mom.

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