"My worst one was right on the money."

The subject is orgasms. The speaker is pretty clearly a man. (Woody Allen, to be exact.) And the time is just as clearly the late 1970s -- that cresting point of sexual liberation when orgasms were an unqualified good, no matter who was having them.

Those really were the days. In our modern times, suggests historian Dagmar Herzog in her new book, "Sex in Crisis," the twin titans of Viagra and Internet porn have made the orgasm so large an imperative that we can no longer consider ourselves complete without one -- which has naturally resulted in making us less likely to achieve one. Today's man must, at every available moment, be rocking his partner's world. Today's woman must demand nothing less than to be rocked.

Small wonder, then, that we have become an anxious nation -- forever wondering if we're having enough sex -- or good enough sex. What if our orgasms really aren't right on the money? "Never have so many Americans," writes Herzog, "worried so much about whether they really even want sex at all."

Being a man, I tend to think sex will shrug off this particular slump and come roaring back for next year's pennant race. But I wonder exactly how many Americans are, as the author claims, on the verge of swearing off coitus. (Is one of them my partner?) Herzog never offers much in the way of hard answers. Which makes the starting thesis of "Sex in Crisis" -- that we are in the midst of a "sexual revolution," or more properly a devolution -- look pretty damned soft, even by the loose standards of sociological treatise. The good news: Herzog has a more interesting agenda up her sleeve than critiquing our ejaculations. She wants to anatomize the subtle and unsubtle ways in which the Religious Right (a rubric that, in her cosmos, must always be capitalized) has warped our sexual politics and forced even the most hardened secular humanists to sing from the Christian hymnal.

"For liberals, sex has become the problem that has no name; one simply does not hear liberals articulate a defense of sexual rights. Instead, what we have witnessed is a coalescing of conservative evangelical and mainstream secular perspectives on sex. The conversation on sex in America -- when sex is discussed in a serious and earnest way at all -- tends largely to adopt the parameters set by the Religious Right."

Assuming this to be the case, how exactly did it happen? Herzog's intriguing and deeply researched thesis is that evangelicals, over the last couple of decades, have beaten liberals at their own game by adapting liberal rhetoric for conservative ends.

As recently as 2003, for example, a certain public figure was arguing that voluntary prostitution was "despicable" because it "demeans the value of women" and promotes "the severe degradation and exploitation of women, the literal rape of countless women around the globe." Was it Andrea Dworkin? Catharine MacKinnon? The correct answer: pro-life Rep. Smith, R-N.J., whose distinctly illiberal purpose was to limit AIDS outreach efforts to prostitutes and sex workers in developing nations.

Or consider these descriptions of the female orgasm: "waves of pleasure flow[ing] over me ... like sliding down a mountain waterfall ... like having a million tiny pleasure balloons explode inside of me all at once." Erica Jong and Xaviera Hollander? Try evangelical sexologists Linda Dillow and Lorraine Pintus. (Even their names are suggestive.) Far from scorning the pleasures of the flesh, evangelical and marriage experts -- recognizing, in Herzog's wry phrase, that "repression alone is not sufficiently appealing" -- have made their careers by hymning the joys of strictly marital sex.

"We think the G-spot should be seen as one more way God gave us to share in the pleasure of sex," announced the Revs. Paul and Lori Byerly, hosts of the online site the Marriage Bed. Evangelicals Melissa and Louis McBurney have endorsed oral sex, mutual masturbation and rear-entry vaginal penetration -- between spouses. The Rev. Charles Shedd has declared that he and his wife, Martha, like anal sex just fine. As Herzog notes, these sex-positive Christians have absorbed from the women's movement of the 1970s and 1980s "an interest in intensifying women's sexual pleasure," as well as "the frustration at male fascination with pornography and emotional nonpresence during sex." The result is a kind of "Christian porn," as sexperts guide their married readers toward the holy land of "soulgasm," where spirit and flesh come ecstatically together. If you follow the rules, Herzog writes, "magnificent sex will be yours forever."

Ah, yes, the rules. A Christian wife, if she wants to keep her husband's mind off porn and his hand off his own penis (onanism is still a big no-no), will have to be a 24/7 tootsie. She is advised to wear sexy lingerie and to keep her legs shaved and her nether region douched at all times. ("Wives," as Jack Jones once crooned, "should always be lovers, too.") And she has to give it up whenever her man comes calling. The example of a woman named "Ellen" is approvingly cited. "[My husband's] purity is extremely important to me, so I try to meet his needs so that he goes out each day with his cup full. During the earlier years, with much energy going into childcare and with my monthly cycle, it was a lot more difficult for me to do that. There weren't too many 'ideal times' when everything was just right. But that's life, and I did it anyway."

In a dismayingly familiar pattern, the needs of wives give way more often than not to the needs of husbands. Writers like John Eldredge, Stephen Arterburn and Fred Stoeker, borrowing from the archetypes of the New Age men's movement, have exhorted Christian men to embrace their Y chromosome, to turn off the Internet and tap into their own "mustang minds," to become "dangerous," "wild at heart." And to somehow remain, in the midst of this testosterone sea, anchored to their wives.

Under these terms, it seems, Christians really can "have it all." But only if others can't have any. As Herzog writes, this model of Christ-sanctioned bliss depends on "the construction of homosexuality as the disgusting opposite of heterosexuality."

And here, too, the religious right found a way to couch its arguments in secular, even quasi-psychological terms. Homosexuality was no longer simply a sin but a disease, eminently curable. "You are heterosexual in Christ," announced a speaker with the ex-gay ministry Exodus International. "No matter how deep your homosexual feelings are, deeper still lies your heterosexuality, buried under a thousand fears." Preying on those fears, Exodus has mushroomed to more than 100 chapters across the United States, and zealots like Dr. Joseph Nicolosi have undertaken "conversion therapy" on boys as young as 3.

Of course, to guarantee truly awesome sex, you have to be more than simply heterosexual. You also have to be chaste, at least until you're lawfully wedded. "Sex is progressive in nature," warns Focus on the Family founder James Dobson. "Kissing and fondling will lead inevitably to greater familiarity ... Tell [boys] not to start the engine if they don't intend to let it run."

That purring engine has become the prime mover behind "abstinence only" sexual education -- perhaps the religious right's most lasting contribution to mainstream society. Where traditional sex ed programs attempted to give teenagers the knowledge to protect themselves in sexual encounters, Herzog writes, "new abstinence advocates use the fear of disease to frighten kids away from sex entirely."

Consider this classroom exercise: "Boys and girls are invited to chew cheese-flavored snacks and then sip some water, after which they are to spit the resulting 'bodily fluids' into a cup. After a game in which the fluids are combined with those of other students, ultimately all cups are poured into a pitcher labeled 'multiple partners' sitting adjacent to a pitcher of fresh water labeled 'pure fluids.' In the final segment, each boy and girl is asked to fill a cup labeled either 'future husband' or 'future wife' with the contents from one of the pitchers."

The Georgia-based program behind all this expectoration received more than half a million dollars in taxpayer dollars, and it is by no means the only such program to benefit. At every turn, the abstinence-only movement has been abetted and advanced by the Bush administration. As recently as 2006, the Department of Health and Human Services was offering grants for programs that teach "the potential psychological side effects (e.g., depression and suicide) associated with adolescent sexual activity" and that instruct students that "non-marital sex in teen years may reduce the probability of a stable, happy marriage as an adult."

"May reduce"? According to whom? Pro-abstinence forces have never been too rigorous in their scholarship; the categorical assertion is their preferred vehicle. (According to the Abstinence Clearinghouse, virgins "invariably do better in their professional and personal lives than nonvirgins.") And when they fail to persuade with fear, they dangle the carrot of future sex. As Herzog summarizes it: "Only those women who have been premaritally abstinent will be truly, deeply, and consistently desired by their husbands in the long years after marriage ... Have no sex before marriage and you will have outstanding sex after marriage."

Once again, a religious argument is being advanced on strictly secular grounds (in this case, the language of women's mags). Fortunately, it can also be refuted on secular grounds. According to a recent Yale-Columbia study, some 88 percent of adolescent virginity pledgers fail to keep their pledge. And while they tend to have sex later than their peers, they are one-third less likely to protect themselves when they do.

But then protection has never been part of the grand scheme. In the abstinence worldview, faltering virgins can still find God. ("It's never too late to be a virgin. No matter what you've done, you can have a secondary virginity, it's there for you to reclaim.") But they cut themselves off from salvation the moment they take the pill or slip on a rubber. As one activist puts it: "There is no condom that can protect you from a broken heart and a shattered dream." Susan Orr, formerly of the Family Research Council and, for a short unblessed time, the deputy assistant secretary overseeing family planning and reproductive health, once declared that contraceptives are part of "the culture of death."

In fact, they are part of something even more troubling to the evangelical mind: a culture of non-procreative sex that has done as much as anything to destabilize the institution of marriage. In their efforts to get this genie back in its bottle, pro-abstinence forces routinely overstate both the success rate of abstinence and the failure rate of condoms.

As Herzog demonstrates, that policy of calculated denial has had particularly ruinous effects in the developing world. Under the guidelines of President Bush's Emergency Plan for AIDS Relief, African countries risk losing funding altogether unless they can show they have earmarked two-thirds of their prevention monies solely for abstinence and fidelity messaging. According to a GAO report, abstinence mandates have significantly reduced outreach to sex workers and sexually active youth, as well as programs to inhibit mother-to-child transmission of the virus -- at a time when HIV has already infected some 33.2 million people around the world.

"What should have been a comprehensive war on HIV," writes Herzog, "instead turned into a war on condoms." Which is only a natural outcome, she argues, of an often overlooked truth: The religious right is "not simply a religious movement or a political movement; it has also, and above all, been a sexual movement."

That it should have used sex as a springboard to power is particularly infuriating to a libertarian like Herzog, who has spent many months delving through the archives of the enemy and has the anger to prove it. Words like "incoherent," "cruel," "mendacious" are flung with increasing frequency as the book progresses, and any pretense of trying to understand or engage the evangelical mind is abandoned in favor of tracking its carnage.

But even as I applaud Herzog for her passion, I wonder: How great is the carnage? Has the religious right really changed our national conversation about sex? Or has it been speaking to itself all along?

Teens, after all, are still having sex. (America has the highest teen pregnancy rate in the developed world.) Gay sex, as Herzog admits, has "lost its power to repulse," and our most populous state has now opened the doors to gay marriage. "Abstinence-only" has been a regression, it's true, but liberal sex educators have pulled off a co-opting trick of their own, creating "abstinence-plus" programs that make abstinence simply one component in a comprehensive array of informed choices.

Even that is too great a concession for Herzog. She hates the fact that "many self-defined sexual liberals now rush to concede that a delay in sexual debut is desirable and that keeping the number of sexual partners in a lifetime to a minimum is an important sign of psychological health and self-valuing ... What's missing is the basic idea that sexual rights are human rights -- for adolescents, for sexual minorities, and for individuals both within and outside the institution of marriage."

For sexual minorities and consenting adults, yes. But what does it mean to say that an adolescent has a "human right" to sex? How can any adolescent in our eroticized culture be said to exercise "sexual self-determination"?

At the risk of sounding like the kind of liberal Herzog dislikes, I don't think it's unreasonable for parents to want to complicate their children's sexual choices, even if that means delaying them. When my 8-year-old son asks me why Jamie Lynn Spears, the star of one of his favorite shows, is having a baby at 16, I'm genuinely torn in how to respond -- not wanting to condemn and not wanting to endorse, either. It's the same discomfort many parents felt at seeing the topless pictures of Miley Cyrus in Vanity Fair. How do we accommodate our children's sexuality? And how far?

The religious right was able to shape this dialogue only because the dialogue was already happening -- and is still going on today, even in the most progressive quarters. It says something about the ideologues on both sides that we can no longer have that conversation without being called ideologues ourselves.