The book is a response to those oh-so-sympathetic harangues directed at twenty- and thirtysomething women who dare to put off marriage and child-bearing (from self-help blockbusters like the “The Rules” to quasi-academic tomes like last year’s “Creating A Life” by Sylvia Ann Hewlett), as well as to the smaller but no less influential group of books declaring that the younger generations are peopled with slackers and solipsists who threaten our democracy, our sense of community, our very way of life.

Watters’s thesis, first served up in The New York Times Magazine in 2001, is that college grads from affluent backgrounds spend the ever-lengthening period before they marry traveling in large packs that provide both emotional and material support. The first half of the book is devoted to insisting that urban tribes exist (to which I kept wanting to say, “We believe you, we believe you, Ethan–and have you ever heard of Mary McCarthy’s ‘The Group’?”) and that they’re a force for good. As for Part Two, called “Love in a Time of Nervousness,” it really isn’t about tribes at all. In this section, Watters tries to demonstrate that the current generation’s “marriage delay,” which tribes may or may not foster, isn’t the bogeyman it’s been made out to be. What unites the two parts is that they both depend on straw men, built by the hard-working trend and self-help pushers mentioned above, for Watters to–poof!–destroy.

Straw man No. 1: In “Generation X”–remember that 1992 novel-cum-doomsday-alert?–Douglas Coupland suggested that the rise in the number of “never-marrieds” among thirtysomethings was catastrophic because people who aren’t devoted to spouses and children don’t give a damn about anyone but themselves. Once he’s scribbled down Coupland’s (rather fusty) background premise, Watters spends page after page documenting the nice things tribespeople do for one another: pay for vacations after gnarly break-ups, paint houses and mow lawns, cheer on and feed members who take career risks.

All this sounds great, really. As someone who’s never had more than a few close friends at one time, I’ve always been a little envious of these sprawling yet tight crews–man, could I use some more easy camaraderie in my life and a few more extra hands to help out when things get rough. But while such caretaking is lovely, it’s only a revelation if you believe that people without family don’t put themselves out for others–and I’ve always believed exactly the opposite. With a 3-year-old already on the ground and another child due any minute, I despair at how much will it requires to tend to anything beyond my own small unit. Indeed, I think children are mainly a selfish endeavor; it’s before they come and after they leave that people have the time and mental space to give generously to friends and the broader world.

Straw man No. 2: Things were so much better in the good old days when everyone belonged to a bowling league or the Lion’s Club or church organizations–or all three! This, of course, is the argument put forth in sociologist Robert Putnam’s famous lament about the “anti-civic contagion” of contemporary culture, “Bowling Alone.” While Putnam seemed to be tapping into a palpable sense of alienation and isolation in American life, his argument was pretty blatantly overdetermined, which Watters quickly jumps on. According to Putnam, the current generation is comprised more of “schmoozers,” who are by definition inwardly focused, rather than the paragons of community-minded virtue from the past he calls “machers.” But who’s to say, as Watters writes, that “maching was more important to civic groups than schmoozing?” Didn’t 40-year-old guys don hats with tassels as much to “get out of the house or, even more selfishly, get a little more business down at the car dealership” as to raise money for the local hospital?

Watters is on firmer ground questioning Putnam’s sunny outlook on the Shriners et al (the racist and sexist underpinnings of many such organizations is yet another issue) than he is trying to show that urban tribes contribute to anything larger than their members’ well-being. Drawing on network theory, he suggests that the weak ties among tribes–one tribesman is friends with someone from another tribe, who’s friends with someone from another tribe and so on–can coalesce into a “politically powerful force.” But the examples he offers aren’t persuasive. Take the Critical Mass demonstrations that began in San Francisco in the late ’90s and gradually spread to other cities, in which bicyclists semiregularly blocked traffic on major streets. There wasn’t one person or group who put out word of the events but instead the news was passed friend to friend via e-mail, thanks largely to urban tribes, Watters asserts. I’ll buy that, I guess, but as he also says, Critical Mass was actually just a giant block party. “[W]hat the protests meant was up for grabs,” Watters writes. “[P]articipants thought that Critical Mass was something of a populist uprising that was to do battle with everything from the spread of SUVs to corporate greed and free trade.” Call me old-fashioned (and perhaps here I should mention that, born in 1964, I’m a tail-end baby boomer) but how can a protest without a point be politically powerful?

Watters also cites the national and international criticism of Nike’s global work practices that gained traction after the giant corporation refused to personalize an MIT student’s shoes with the word SWEATSHOP. The whole thing started when the guy sent his e-mail exchange with Nike to 12 “friends.” But just about everyone I know has her computer set so she can forward a message to at least 12 friends and/or colleagues, and the vast majority of them wouldn’t qualify as tribesman. Did the MIT student have a clan, or merely a 12-member “group list”? Who knows? Similarly, if Watters were writing his book today, he’d surely credit his pet notion with Howard Dean’s remarkable rise among Democratic presidential hopefuls. But as dozens of commentators have noted, Dean’s success may be no more than spectacular testimony to e-mail as a communication vehicle.

Straw man No. 3: The male of the species is hardwired to spread his seed far and wide and thus is loathe to settle down; gals are compelled to land a single “resource provider” to help them tend to their progeny; hence, the mating strategies of the two sexes inherently conflict. If you haven’t heard this sociobiological chestnut by now, you’ve been living in a cave for at least the last decade. But somehow Watters just recently stumbled onto it, and he fritters away a frightening number of pages recounting how he tried to argue his female friends (and even new girlfriends) into conceding that a cowboy’s gotta ramble, lest he deny his animal destiny. Then he takes us with him on a trip to Austin, Texas, to meet the guru of the theory, provocateur/professor David Buss, who–and the reader can see this coming from the get-go–disabuses Watters of his foolishness. Even if this particular bit of evolutionary biology is correct–and many other scholars debate it–modern men aren’t “slaves to any particular sex role created by evolution,” Buss wearily counsels. Ancient drives aside, big-brained humans weigh many factors when choosing whether to be monogamous or sleep around.

(Throughout this dreary discussion, Watters apologizes for being such a “nitwit,” but the reader doesn’t forgive him. Why bother including this self-indulgent, unenlightening, and deeply tangential section at all? Thank the agent who told him he had a book–he just had to “expand” on his thoughts enough to fill a respectable 250 pages.)

Straw man No. 4: Women who delay marriage are sure to end up manless, childless and miserable. Perhaps because this idea, however fallacious by the numbers, still has legs, I found Watters’S knock-down here more useful than elsewhere. As Elle writer Rachael Combe noted in an incisive critique of Barbara Dafoe Whitehead’s misleading 2002 tome, “Why There Are No Good Men Left: The Romantic Plight of the New Single Woman,” about 97 percent of single, white, college-educated women will marry, and “78 percent are likely to have kids (the same as working married women of lower income and education levels).”

Watters includes similar observations (though without Combe’s precise data), but his real strength is that, strangely enough, he seems to understand how single women live and think better than the older, female authors who keep churning out books warning that today’s young ladies are wasting their prime husband-catching and babymaking years.

“Women weren’t just treading water during their single years,” Watters writes. “The statistics, and pretty much all the anecdotal evidence I found, pointed to the conclusion that these women were becoming remarkably self-sufficient and confident adults … What will seem weird to future generations will be that we perceived the personal and professional accomplishments of women as being in conflict with their hopes of finding happy marriages … For men, societies have long assumed that their solo accomplishments made them more valuable as mates.”

Watters pragmatically concludes that the “record-setting delay” in marriage will surely mean that a somewhat lower percentage of couples will be able to have children, but where last year’s infertility–Cassandra Sylvia Hewlett sees a “mother lode of pain and yearning,” Watters concludes, “I doubt there will be a large number of people who go through their middle years mourning the children they never had. The human creature is more resilient, forward-looking, and innately hopeful than that.” Maybe the two authors simply hold contradictory but equally valid opinions about the same “fact,” but the lengths to which Hewlett went to twist the research to bolster her dark outlook–and my own biases about human nature–persuade me that Watters is more accurately depicting reality.

Still, “Urban Tribes” will only be welcome by those who truly buy the crude, data-lite generalizations that publishers keep peddling. For those who are more skeptical, it reads as thinly and tediously as any of the books Watters so diligently tried to counter.