Forgive me for being cynical, but I have a hard time believing that the White House and Michelle Obama are really upset by the portrayal of the first lady that emerges in Jodi Kantor’s new look at the president’s marital union. In the annals of irregularities that first ladies have been justly or unjustly accused of, sparring with a chief of staff — particularly one as combative as Rahm Emanuel — hardly registers as shocking or unexpected.

Dancing on a Cabinet Room conference table (though, of course, people loved that in Betty Ford), firing longtime White House staffers, consulting an astrologer about the presidential schedule, tolerating affairs, winging a book at a Secret Service agent, succumbing to substance abuse, engaging in a same-sex relationship, suffering from mental illness, secretly running the country after the president was felled by a stroke — now those are salacious tidbits and charges, some of them fictional, maybe, but many of them moments of real, even operatic drama in the narrative of presidential marriages.

Michelle Obama should be congratulating herself on her good fortune.

Reading Kantor’s book, I found myself reflecting on something other than the burning question of whether the inevitable standoff between Loyal First Lady and Trusted Professional Staff did or did not (but probably did) occur. How atavistic and constricting and bizarre the office of first lady is, what an impossible position these women are put in, and how it will be a good thing for all of us if and when a first lady is permitted to get a part-time job, maybe telecommuting from the East Wing, somehow finding a separate domain into which to direct all that productive energy.

Marriage is the real topic of Kantor’s book. The Obamas embody the latest trends, yet the White House imposes an outdated marriage model, almost Victorian, which is why we always come back to this conversation about meddling. What other choice does a first lady have but to meddle, since she really can’t do anything else?

When Barack and Michelle Obama married in 1992, they reflected the evolution of marriage in the United States. At that time, the postwar model — in which a woman married up, if she could, to a man who had more education and more earning potential — was giving way to a model in which men and women married, if they could, a spouse with the same level of educational achievement. Nowadays, as sociologists have shown, what men and women want is to marry somebody with the same degree set. This was true of the Clintons, and the Obamas are also a perfect example: both Ivy League grads, both Harvard law degree holders, both ambitious and full of potential.

But after her husband’s big convention speech and successful Senate campaign in 2004, segueing quickly into his presidential bid, Michelle found herself teleported back to a 1950s kind of marriage: a model in which a woman with intelligence, education and an overabundance of administrative energy was obliged to content herself with living through her husband and devoting herself to his advancement.

This is what we saw as Michelle cut down her work days, eventually leaving her job with the University of Chicago Medical Center and jumping into the campaign fray. Then she landed in the White House and was transported further back in time, to an almost 19th century version in which the wife is supposed to be the happy helpmate to her husband, a reservoir of domestic replenishment. What the president’s aides wanted, Kantor writes, was for her to be a partner who welcomed tour groups and “buoyed the president’s spirits.” What you see in Kantor’s narrative is the extent to which husbands and wives in the White House are obliged to inhabit separate spheres, in which the world of work belongs to the man, and home and hearth to the woman.