Turmoil generated by the Air Force's decision to accuse its first female B-52 pilot of adultery, among other things, has cast the old sin into a fresh spotlight.
What's revealed is a cultural ambivalence about adultery, but also a growing recognition of the high price infidelity exacts from families and society as a whole.
"I don't think it's as stylish as it was in the '70s," says Frank Pittman, author of "Private Lies: Infidelity and the Betrayal of Intimacy."
In a country built on a Judeo-Christian foundation, Americans overwhelmingly still believe adultery is wrong, as the Sixth Commandment makes clear. But they're also not willing to cast the first stone, many for fear of flying glass. Although few surveys concerning adultery are considered completely reliable, they show anywhere from 25 to 70 percent of married men admit to having been unfaithful. For married women, the number falls between 15 and 40 percent.
But the statistics belie a growing backlash against adultery, experts say, not so much because of the sexuality involved, but because of the dishonesty.
"The people who get comfortable lying to their partners are training themselves in irresponsibility and deceit," says Dr. Pittman. "They're turning their partnerships into adversarial relationships and doing terrible things to their own character."
Indeed, the issue of honesty is at the heart of the case against Lieutenant Flinn, the pilot whose career now hangs in the balance. She fell in love with a civilian soccer coach, who she says said he was legally separated when he wasn't. Perhaps because of that lie, the case has generated an outpouring of public sympathy for the young lieutenant.
But the Air Force is adamant that Flinn should be punished because she lied to superiors about her relationship with the man and disobeyed an order to keep away from him.
The case exemplifies the difficulty of reconciling emotional affairs of the heart with strict legal sanctions. While adultery is illegal in half of the states in the country, it is rarely, if ever, prosecuted.
"I can think of four, maybe five, cases of criminal prosecution during the last 15 years," says Katharine Silbaugh, a law professor at Boston University and co-author of "A Guide to America's Sex Laws."
The introduction of "no-fault" divorce changed the notion of marriage from a permanent state that the larger society had a stake in supporting to a primarily private matter in which either mate could dissolve the marriage, regardless of what the other thought. As a result, says Ms. Silbaugh, it no longer made sense to criminally prosecute someone for what was seen as a private matter.
Most Americans agree the courts are not the place to deal with adultery. But surveys show there's a growing backlash against infidelity, particularly among people in their 20s, many of whom are children of divorce. Still, for them, the issue is more one of personal integrity.
BUT in the military, regulation of private lives is much more accepted. "Adultery is a chargeable offense under the Uniform Military Code of Justice, and anyone who volunteers, and I underline volunteers, knows that," says Capt. Byron James, an Air Force spokesman at the Pentagon.
The Air Force insists that it must hold its soldiers to a higher standard than in civilian society. Amid battle, honesty, discipline, and honor are central to survival.
"I think [the Flinn case] is a short-term embarrassment for the Air Force, but a long-term gain," says Charles Moskos, a leading military sociologist at Northwestern University in Chicago. "They say they're holding their people to a higher a standard, and to their great credit, they're taking on a high-profile case to prove it."
The American military has been putting more emphasis on strengthening families in recent years. One result is that the number of prosecutions for adultery, at least in the Air Force, has quadrupled. In 1985, only 15 courts martial involved adultery. In 1996, 67 courts martial involved infidelity.
The Air Force is quick to note that adultery prosecutions make up less than 1 percent of all courts martial, a statistic that hasn't changed significantly during the past 10 years. Air Force officials also insist there has been no change in the way in which prosecutors use the charge adultery.
But critics disagree. Some feminist groups contend the military deals with infidelity by its senior male officers very differently from the way it metes out punishments to junior officers and women.
"They really lower the hammer on junior officers and enlisted people, particularly the women," says David Clemm, a West Point graduate who became involved in the issue after the Air Force charged his daughter with adultery.
A young lieutenant, she had reported that she was sexually harassed by her direct supervisor. Instead of the investigation she'd anticipated, he says, she was accused of having an adulterous affair with the squadron leader to whom she reported her trouble. Both denied the allegation, but both were brought up on adultery charges. The squadron leader was court martialed and found guilty of having an "inappropriate relationship" with a subordinate. He is appealing. Clemm's daughter's case is under investigation, and she has asked to retire from the service.
Mr. Clemm is working with several congresswomen to establish an independent civilian commission to examine how the military deals with issues such as sexual harassment and adultery. While it's too late to help his daughter, he says, "we can hopefully do something for the women still in the service and those yet to come."
Most analysts agree it won't be easy to find a solution, particularly in the military. "Locking people up for their sexual behavior is not the answer," says Pittman. "What we've got to do is make adultery unfashionable, and that's something best done by the media."