What is hip?

You’d have thought it was one of the other life-or-death issues currently bedeviling us, like war, stem cells, gay marriage or the red state/blue state post-mortem.

But what had people gnashing their teeth, if not altogether up in arms the other night at Westwood’s W Hotel, wasn’t what was happening in Iraq or in Ivory Coast or, for that matter, Ohio.

To hear writer John Leland tell it, it was a different bend on the culture wars. “Everyone came up and they were really challenging, like: ‘Well, come on! Isn’t this just about self-destruction and killing? Nihilism? Why aren’t you writing about nihilism?’ ”

You’d have thought Leland was really on to something truly transgressive. But his new book, “Hip: The History,” is an earnest look at a phenomenon that tends to prefer to wriggle out of definition. At nearly 400 pages, it is not just a history of hip; rather it is a history of popular culture in America and how blips in hip have shaped everything from cartoons to noir to the Internet -- with commerce never too far behind.

The book has already prompted some spiky responses. “At a reading in New York,” he continues, “someone says to me: ‘I noticed that you didn’t use Anatole Broyard’s 1946 essay, “Portrait of a Hipster.” That seems to me like a missing piece.’ And I loved that. He was like a 60-year-old. In a beret.”

Of course he was.

For those deeply invested, “hip” is nothing if not subjective. Who or what is “authentically” hip has always been something hotly contested -- fighting words. That doesn’t even scratch at the notion that the word “hip” (or “cool” or “edgy,” for that matter) often translates into just the opposite after it broadcasts wide, is suddenly everywhere at once. Such is the nature of the street.

“Cool used to be a symbol of escape. An unassailable castle, at least that was the sense,” says Lewis MacAdams, who too tackled this ever-changing territory a couple of years ago in his elegant and worldly book, “The Birth of Cool.” “Hip is angry and wise to the ways of the world,” he says. Indeed, nowadays, what hip is -- or what it was and has evolved into -- is often elusive, slithery.

The idea then, says Leland, was to start conversations, not finish them. “I thought if this were the last word on hip, that’s bad,” says Leland, who is in the midst of taking hip’s temperature across the country promoting his book. “My hope was that it would be the start of an argument or a piece of an argument. If there’s value here, it will be in what people add to it.”

Leland is ready, come what may. He’s busy diagraming all of this over lunch in a shadowy Silver Lake bistro that overlooks Sunset Boulevard’s scruffy eastern end. To his now well-seasoned eye, it looks a lot like much of the post-hip enclaves of the last few years -- dotted with coyly named boutiques selling neo-retro garb, music outposts that deal in vinyl and a surfeit of cafes for loafing.

Leland takes in the street theater: Dudes in trucker hats slouched in front of laptops, girls with blue-black Bettie Page bangs and combat boots trudging to the bus stop are juxtaposed against the guy with the suede top hat, beard and ‘60s flight bag, rushing past them, bent toward something else.

According to hip calculus, it probably would have been hipper if this chat were taking place two blocks east, in Echo Park, as opposed to Silver Lake, which is oh, so five minutes ago. And, according to Leland’s rubric, there is nothing worse than being five minutes ago.

But hip is cyclical. It’s subjective and elusive -- and always au courant. This season alone offers two very different books strolling bohemia’s picturesque territory -- Leland’s comprehensive history charting the evolution of the word as well as Laren Stover’s whimsical, tongue-not-completely-in-cheek “Bohemian Manifesto: A Field Guide to Living on the Edge” -- which tracks the lifestyle.

What both these recent books remind us -- whether it is called “cool” or “hip” or “boho,” or recoils from labels all together -- is that what used to be considered “outsider culture” is something that is constantly being picked apart, redefined or utterly reimagined.

Those hipsters who rolled up in their ironic ’62 Ford Fairlanes in the ‘80s look down two decades later on the guys with Beck hair, who are driving up their rent. But what the Fairlane folk forget: When they arrived, there was that crop of earlier settlers who were packing up, fleeing their soon-to-be ruined scene.

One hip enclave is much like another. And so is its history: What’s happening in Silver Lake or Echo Park is happening in Williamsburg, in New York or SoMa in San Francisco. “But for the people who moved in today the glory days are right now,” Leland explains. “The people who move in two years from now will be really annoying and fake. I think authenticity and hip are almost exclusive. That kind of purism, to me, it curdles immediately. It gets to be that nerdy, hipper than thou, band boy, record collector types.”

Former editor in chief of Details and now a reporter for the New York Times, Leland, 45, says that he by no means set out to crown himself the arbiter of what was hip and what was over. What he didn’t want it to be was “a snobby book about cool people by someone who never got to be one.” Even his look is hedging, a conflation of eras and styles and schools -- a skinny-lapel jacket, cigarette leg trousers, Pumas and, of course, some abstraction of facial fuzz.

Hip is the story of proximity. What happens “in the merge.” Its origins lie in the language of West African slaves, in the Wolof verb hepi (“to see”) or hipi (“to open one’s eyes”). It began, Leland says, as one of the tools Africans developed to negotiate an alien landscape, to carry subversive intelligence that could only be understood by insiders.

The friction of blacks and whites’ early cultural exchanges formed hip’s roots. Leland then taps into what he sees as the further “major convergences of hip.” The flashpoints include the birth of blues and minstrel shows -- “black and white Americans’ first responses to one another” -- coupled with the emergence of Thoreau, Emerson and Whitman, who celebrated individualism and civil disobedience; the bohemia of Greenwich Village, the Harlem Renaissance and the Lost Generation. The tucked-away basements of bebop and the Beats was another marker, as were the punk-inspired Do-It-Yourself movement of the ‘70s and ‘80s and b-boy culture, the nexus of cyber-cool and the birth of the re-mixers, DJs and Turntableists as pop stars.

“It wasn’t so much about discovering fresh that there were these musicians called bebop musicians,” he says, “but trying to discover the connections between them and other things” -- from Ralph Waldo Emerson to Ralph Ellison to Louis Armstrong, and William S. Burroughs to DJ Spooky.

The book is far-reaching, a trip that might even be a match for Jack Kerouac’s tireless speed angel Dean Moriarty -- the engine of “On the Road,” one of hip’s classics. Moriarty, whose template was Kerouac’s wild-child alter ego, Neal Cassady, was singular, not something that could be stamped out of a machine, though generations have shambled after that image, trying. The figures who live just along the seams, who thrive, in the margins: Charlie Parker, who began to “hear music in his head” that didn’t exist in the world around him, or later, Bob Dylan, who “wanted things no one even knew existed.”

Within all this hard-sell cacophony, it’s that dedication to things unseen that Laren Stover wants to celebrate. Stover’s book has a lighter heart. At the outset of her new field guide, she proclaims that Bohemia is about living beyond convention; it is not mindful of hip’s currency, rather its concerns revolve around living out of the norm.

“There’s a bit of idealism, but I don’t think that it is always rebellion,” Stover says. “Bohemia is an atmosphere, a way of life, a state of mind,” she writes.

She traces the usage back to writer Henry Murger, who brought the term to the mainstream when his play La Vie de Boheme debuted in Paris. “He gave the label to the eccentric and socially unorthodox,” writes Stover, “poets, painters, absinthe drinkers, dandies on the fringe -- any oddball qualified.”

True bohemianism is not a trend, she explains. It’s not a pair of boots or a cap cocked “just so” like you saw it on MTV. It’s a way of life. For her it is her crooked stairway, her black rotary telephone, seeing the gifts of imperfections. “The brocade of everything that surrounds me.”

Like Leland’s conclusions about hip, Stover sees “bohemianism” as a mosaic of possibilities shaped by what it brushes up against: “Bohemianism is more than an attitude. It’s the apolitical freedom of ideas, clothing and behaviors gently outside the norm. It is an elixir of undisclosed ingredients....”

For Stover, bohemianism was unavoidable. Her parents lived in a cold-water flat on the Bowery in New York with “a pull-chain toilet in the hall (shared) .... and a ... sociology major renting out the back room.” With humor and poetry fueled by historical overview, Stover sketches various “textures of bohemia,” the many profiles -- “nouveau, gypsy, dandy, Zen and beat bohemians” among them.

Lushly illustrated, there are subchapters on “Counterculture Cuisine” and “Nudity”; “Bohemian Shelter” and “Asylum -- Home Away From Home.” It might first sound as if Stover is just having a little fun. But her intent is deeper.

“I wanted to celebrate my brand of alternative living. Not the down-and-out parts, but the splendor and glitter of it,” she says. “I wanted it to be a catalyst for other people. Our culture is so obsessed with brands and labels and mass culture. You can’t help but be affected by it,” she says.

Being a true bohemian is being an outsider, Stover says. And sometimes it can be to the point of ostracism. It’s as far away from “in” as you can run. It’s Michael Moore, say, or Theo Van Gogh, who was killed in Amsterdam earlier this month after the release of his film about women and Islam.

“It takes a lot of courage. You find yourself following your own road, your own passion. You have to do it. Even if you are feeling unpopular or threatened. There is nothing that can keep you from going that direction.”

In this post-hip era when marketers unleash “cool hunters” to spot the most minute shift in the culture, that in-between space of hip or cool has often vanished, gone before the thought is fully articulated. And right behind them, “viral marketers,” who install themselves at the hottest nightspots to stealthily hawk a new product. Such are the ways of our times.

Attempting to bottle the unbottleable or, at the very least, that essence, and selling it like snake oil is what hip feels like to many today. It’s not the suede top hat, but the turned-up cuff, blunt short bangs or the irony of a trucker’s cap; it’s a pose that too often feels contrived.

All told, it’s probably easier to be hip now than square.

“Any group who is ‘hip’ or ‘cool’ now is simply part of advertising,” MacAdams says. “It’s so conscious,” he says. “Before, it was a destination. Now it is a sales tool. Cool used to be a symbol of escape. Cool was a province of few and a desire of everyone. Now it is a province of many and a desire of nobody.”

Yet hip, maintains Leland, has never been pure. Hip and advertising have long been bedfellows. Hip, he writes, is “a trick to make people think they’re rebelling when they are just buying stuff.” What’s most changed, says Leland, is context.

“Things started out with minority little cells in a world that was hostile to what they were doing. You were a drug ‘fiend,’ you were a sex ‘fiend.’ You were a criminal or an outlaw. Now you’re a cool hunter. A tastemaker.”

Stover is feeling less cynical. For the true bohemian, it’s a self-appointed, if solitary, path: “To evolve intellectually and spiritually, you have to let go of old ideas and things. I don’t care if it means that someone is going to get in the spirit by wearing a black sweater and reading ‘Howl’ or Anais Nin. Exploring it is a beautiful thing.”

In the end, really, says Leland, “performance is part of all of our lives. But there has always been a difference between an original performance and a derivative one. So I don’t make the distinction between authenticity and put on,” he says. “But I think we can tell the difference between a good show and a tired show.”