For a stretch this past summer, you couldn't fire up your laptop without encountering news of yet another sordid sex scandal involving a powerful, allegedly smart (and invariably elected to office) man.

Even the unshockable among us were, well, shocked to discover that actor-turned-California-governor Arnold Schwarzenegger had not only cheated on Maria Shriver with their longtime housekeeper but also secretly fathered a child with her. And that New York congressman Anthony Weiner was tweeting photos of his privates to a college student, among others, within a year of marrying political aide Huma Abedin.

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But those are just the latest inductees into the cheating hall of shame. Let's enumerate some of the raunchy revelations of the past few years, shall we? John Edwards (fathered a child out of wedlock while his now-deceased wife was battling cancer); South Carolina governor Mark Sanford (misused state funds to visit his mistress in Argentina); Louisiana senator David Vitter (admitted to hiring hookers); New York governor Eliot Spitzer (hookers, again).

What's most confounding is why. Many of these men seemed to have it all—bright wives, bright futures—until their appalling antics sent their careers and marriages into a nosedive. With the help of psychologists and behavioral experts, we examine what's behind this epidemic of idiocy.

No. 1: Why Some Politicos Can't Keep It in Their Pants
It's been said that Washington, D.C., is Hollywood for nerds. After all, it's usually not the hot jock who goes into politics. It's the yearbook editor, the debate team champ, the class president, the guy who likely exited high school with his virginity intact.

When a Husband Cheats


"Here's a guy who was always shoved into lockers, and suddenly now he's in power, and power is status," says Debra Lieberman, an evolutionary psychologist at the University of Miami. Once a guy like this gets a taste of the aphrodisiacal powers of that status, the temptation grows.

"Politicians have become like rock stars," observes Michael Kimmel, a sociologist at the State University of New York at Stony Brook and author of Guyland. "They have groupies. They're celebrities. And celebrity makes people seem very sexy. So it's really the revenge of the nerds."

As Kimmel sees it, the crucial piece is this: "When you have power, you feel like you deserve to be listened to, you deserve to have people fawning over you. And I think that propels a lot of guys to suddenly feel they can walk into a room and get any woman they want. There's an enormous sense of entitlement."

Can guys really stay faithful?


Of course, there's also a fine line between ego and insecurity—and, Kimmel surmises, those conflicting feelings are more common in politicians than in, say, rock stars. That combination, where you feel both undeserving and entitled, can fuel bad behavior.

No. 2: Men Are Better at Living Dual Lives
Why, then, don't female politicians fall prey to such icky inclinations? We haven't heard that Hillary Clinton or any of our 17 female senators or 76 female U.S. representatives hired male hookers, tweeted racy photos, or did other reckless stuff. "These women are not narcissists," says Judith Orloff, M.D., an assistant clinical professor of psychiatry at UCLA and author of Emotional Freedom. "They may have narcissistic traits, but they also have empathy, which true narcissists don't have." Another theory? "Women generally don't need to remedy having been a nerd by eroticizing their power," says Kimmel. "Men in power often experience sex as a way to self-demonstrate their worthiness. Women don't do that. They don't tend to separate love and sex. It has to do with which parts of our identities we're willing to compartmentalize."

Why are women struggling with faithfulness?


In our industrial society, men have been taught to separate work from home. But their brains are also a factor. "Information from the left brain to the right brain travels better in women than in men," explains Vicky Luine, Ph.D., a neuroendocrinologist in New York. "So maybe men can keep the right [intuitive] and left [analytical] functions separated more easily." They may be hardwired to compartmentalize areas of their lives more effectively (and with less guilt).

No. 3: Testosterone is Like Crack to a Narcissist
In a way, men really do think with their penises. "A man gets a testosterone boost every time he succeeds in something," says Orloff. That is, he gets a shot of the same chemical that jacks up his libido. "So it's because of an 'addiction' to testosterone that men keep going for more and more success." Meaning, when they succeed at something, they get a rush that says, "I'm powerful! And so is my penis!"—which can send them looking for other, more tawdry avenues to success. "Women don't have that correlation so much in their brains. They're more into accomplishment. There's less of a sexual connection," says Orloff. Luine agrees: "Testosterone contributes to a lot of the things men do in terms of seeking sex and aggression. Females, of course, have far less."

Is He Keeping Secrets?


In addition to testosterone, a man's prefrontal cortex comes into play (or should)."That's the part of the brain that causes other brain areas to be restrained," says Luine.

"The prefrontal cortex is really trying to get rid of that thrill-seeking behavior—all the negative things that can lead to trouble."

Unfortunately, it's one of the last parts of the brain to mature. And because males develop later than females do, their prefrontal cortex develops later as well. Which, according to Luine, accounts for a lot of impulsive behavior in teenage boys.

But shouldn't a mature guy's prefrontal cortex be fully developed? "It should be," says Luine, "but in some men it doesn't seem to be. There's no definitive reason why—it could be a physiological problem, like low glucose or blood flow, or an environmental issue, such as a toxin or a blow to the head. And while the same things could influence female brains, it seems that males are more often affected."

From an evolutionary point of view, says Lieberman, "being at the top does change very much how men behave and act—perhaps in ways that make it seem as if their behavior can go unchecked. But in the modern world, there are checks. Like a legal system. And the media. And wives.

No. 4: They Pull the Pin on Their Own Pressure Grenade
Then there's the impact of stress. "Stress can act on the prefrontal cortex to impair function," says Luine, "much like chronic tension impairs learning and memory. So maybe these guys are under so much stress that their prefrontal cortex is shutting down from secretions of cortisol, the stress hormone." And it is true, she adds, that women handle chronic nuttiness better than guys do, because estrogen helps alleviate the effects of cortisol even under crazed conditions; it helps keep the phone lines in the brain humming. "Also," says Orloff, "women have oxytocin, the hormone that helps women bond and find solace in connection. Men don't really have much of that hormone either." So when it comes to a stressful situation—because surely one can argue that Hillary Clinton, for example, has a lot more stress than Anthony Weiner ever did—there's a function in the brain that allows a woman to handle it in a less destructive way.

Another disadvantage some men seem to have: They don't know when to say uncle. The pressure on them grows and grows, and rather than find some way to deal with it, says Orloff, they sabotage their careers. "It's an unconscious motivation," she adds. This kind of self-destruction can take many forms, whether it's stealing from the company's bankroll or coming to the job reeking of beer-for-breakfast. For many politicos, though, the implosion is specifically sex-centric. Explains Orloff: "Ego-driven men tend to go out with a massive explosion. In their minds, sex makes them a big man with power. They don't want to be caught stealing or coming to work drunk. It would be demoralizing and doesn't fit with their image."

In other words, being busted in a sex scandal is the preferable escape hatch from boiling-point stress.

Smart Wives, Stupid Husbands
Why would guys with such fabulous, accomplished wives cheat down? "The narcissistic part of them wants a dependent woman who idolizes them," says UCLA's Judith Orloff, M.D.

So if you're a strong, successful woman who's involved with a strong, successful guy, how can you relate to each other in a mutually beneficial way? You want to be able to be your wonderful, powerful self—but knowing that an insecure man might be tempted to go bimbo hunting, it's in your best interest to avoid having competition overrun the relationship.

"Research shows that relationships improve when we can share our successes with our partner," says W. Keith Campbell, Ph.D., author of When You Love a Man Who Loves Himself.

"So when you have a great day at work, the person you want to share it with is your partner. When you maintain a close relationship, your success feels like his success—and vice versa."

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