Editor's note: Stephanie Coontz is Director of Research at the Council on Contemporary Families and teaches history at The Evergreen State College in Olympia, Washington. Her most recent book is "A Strange Stirring: The Feminine Mystique and American Women at the Dawn of the 1960s."
(CNN) -- How could they not have known they were asking for trouble? In the past few years, Rep. Mark Souder of Indiana had an affair with the staff member who had helped him produce a video promoting sexual abstinence. South Carolina Gov. Mark Sanford flew to Argentina for an extramarital tryst, instructing his staff to tell the press he was hiking the Appalachian Trail. Sen. John Edwards tried to pass off the daughter he fathered as the love child of one of his aides.
And now a stockpile of sexy e-mails has simultaneously brought down the head of the CIA and delayed the nomination of the top U.S. commander in Afghanistan to head NATO.
Many Americans believe these scandals reflect a precipitous decline in respect for marital fidelity. If anything, however, such respect has never been higher. In a 2006 poll by the Pew Research Center, 88% of Americans said adultery was immoral -- a higher number than for any other of 10 unsavory behaviors they were asked about. According to a 2009 Gallup Poll, only 6% of Americans believe extramarital sex is morally acceptable.
Tolerance for male adultery is certainly at a new low. In letters and diaries written during the Colonial and Revolutionary eras, men routinely bragged about their extramarital conquests -- even to the brothers and fathers of their own wives! In the 1850s, it is estimated that New York City had one prostitute for every 64 men, while the mayors of Savannah, Georgia, and Norfolk, Virginia, put the numbers of prostitutes in their cities at one for every 39 and 26 men, respectively.
As late as 1930, Somserset Maugham's play, "The Constant Wife," was considered shocking because the heroine confronted her husband about his affair instead of simply ignoring it, as most women in polite circles did.
President Thomas Jefferson fathered a child by his mistress. So did Warren G. Harding, who also carried on an affair with the wife of a family friend. Gen. Dwight Eisenhower had a long-term relationship with the woman who was his driver in England during World War II. CIA Director Allen Dulles, according to his own sister, had "at least a hundred" affairs, including one with the queen of Greece. President John F. Kennedy's affairs and one-night stands may have numbered even more.
But times have changed. The press and political insiders no longer turn a blind eye. So why do men continue in behaviors that now carry so much risk of exposure and punishment?
Part of it is probably a sense of entitlement. Powerful men have "people" to take care of the mundane details of life. They are briefed on the names and backgrounds of whomever they meet, told when it's time to leave, and extricated from awkward encounters. Someone else keeps track of appointments, money and time, fetches whatever they have forgotten at home, makes excuses when they change plans, and picks up after them when they leave a room. No wonder they get careless about picking up after their indiscretions as well.
But why do equally powerful women so seldom engage in such risky affairs? Some believe that the very qualities that make men successful also make them vulnerable. Powerful men are rewarded for being risk takers, a political consultant once told me, whereas women feel more need to control their emotions and impulses if they are to succeed. There is some truth to this. But I think the answer is more complex, and in some ways sadder.
After all, these men don't necessarily take such risks in other areas where emotions run strong. Political leaders calibrate their positions, moral convictions and emotional impulses with a degree of calculation that would put Machiavelli to shame. Many even shove aside their most deeply held beliefs at the faintest hint that these might expose them to risk.
As someone who has studied the evolution of love, sexuality, and marriage over the centuries, I believe the frequency of these sexual scandals reflects the fact that many men and women have still not fully incorporated into their daily emotional lives the new ideals about gender equity and mutuality that have emerged in the past 40 years.
Today many -- perhaps most -- men sincerely want to marry women who are partners rather than subordinates. And women now want careers of their own, whether paid or unpaid, rather than defining themselves entirely through a husband's achievements. Yet many of our romantic fantasies and cues for sexual arousal are still shaped by the unequal division of roles, power, resources and prescribed character traits that prevailed from the early 19th century up through the 1960s.
Before industrialization moved production outside the household unit, husbands and wives were partners in home-based production, equally responsible for provisioning the household and dealing with the details of daily life. But the experiences and emotions of men and women diverged as men began to earn money outside the home while women concentrated on meeting family needs.
Gradually, women came to see success, prosperity and status as only attainable through the achievements of men, while men became accustomed to receiving love and admiration for possessing skills, resources, and knowledge to which women did not have access. Women began to equate admiration with attraction; men began to equate being looked up to with being sexually potent. For 150 years, romance novels and the mass media have reinforced this confusion.
I think this pattern helps explain why so few women are tempted by the adoration of younger acolytes but often fall for superiors or mentors, while many otherwise happily married men become so intoxicated by admiration that they risk their careers and families for its temporary rush. President Bill Clinton couldn't resist the hero-worship of a White House intern. Then-House Speaker Newt Gingrich carried on an affair with an admiring female aide while trying to impeach Clinton for lying about a similar indiscretion.
Presidential candidate John Edwards fell for the woman who followed him around with an adoring camera as well as an adoring gaze. Rep. Anthony Wiener apparently thought any woman who admired his political views would be turned on by an unsolicited picture of his crotch. And like his CIA predecessor Allen Dulles, whose affair with journalist Mary Bancroft was based on the excitement of what she described as her "overwhelming admiration," David Petraeus bonded with his own worshipful biographer.
Some of the men involved in these scandals are clearly pigs. Some of the women are opportunists. But most are otherwise decent people who have not yet been able to adjust 200 years of conditioned sexual responses to our evolving emotional and intellectual preferences. The challenge facing modern couples -- not just the men and women in these scandals -- is to root out our old psychological habits and incorporate our new expectations of love and marriage into our deepest emotional core.
We will know we have made progress when equality and friendship become more sexy than adoration and uncertainty.
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The opinions expressed in this commentary are solely those of Stephanie Coontz.