The idea driving discussion in the book business these days is a purely capitalist trope masquerading as a populist cause. It’s being taken up by young digital gurus and aged captains of mega-retail alike — people who are either drunk on new technology, or happy, in the midst of a recession, for an excuse to hide their agenda — and all agree in proclaiming publishers who resist are evil and authors who do likewise are patsies. It is the idea that a book should cost ten bucks, no matter what. Doesn’t matter what kind of book it is, who wrote it, how big it is, what the format is, the quality of the work or even of the paper it’s printed on — all the things that drive what it cost to make a thing. Apply this notion to other manufactured objects and it would be scoffed at as lunacy. Really? All cars should cost $10? All beers? All clothes? I won’t even get into discussing how this dictates that the manufacturers and creators of those objects — after all, the only people with a financial stake in a business where everything is returnable — have no say in that valuation. But there you have it: The book reduced to a thing of no inherent actual quality, just a price.

As I say, it’s an idea that’s dominated not just conversation but actual development in every level of the industry — of everything from new business models to new artistic formats — more and more of late. But it really grabbed the book business by the throat last Thursday when Wal-Mart announced it was taking on Amazon.com.

As a Wall Street Journal report by Miguel Bustilo and Jeffrey A. Trachtenberg details, it began late last Thursday when Wal-Mart “launched a brash price war” by announcing it would sell “10 hotly anticipated new books for just $10 apiece through its online site, Walmart.com.” It also announced it was selling 200 bestsellers for 50% off list price.

“Hours later,” continued the Journal report, “Amazon matched the $10 price, squaring off in a battle for low-price and e-commerce leadership heading into the crucial holiday shopping season. Wal-Mart soon fired back with a promise to drop its prices to $9 by Friday morning–and made good on that vow by early evening Thursday.”

“If there is going to be a ‘Wal-Mart of the Web,’ it is going to be Walmart.com,” Walmart.com CEO Raul Vazquez tells the paper. “Our goal is to be the biggest and most visited retail Web site.”

As Trachtenberg and Bustillo astutely note, “The price war sent shivers through the publishing world. Wal-Mart’s move, and similarly low prices for electronic books, may ultimately condition consumers to expect new titles to cost $10, a price that would force the publishing industry to re-scale its entire business, including the advances paid to writers.” One “book executive” tells them, “The endgame is rather scary for authors.”

The point is hammered home when they try to get a “big author … looking on the bright side.” Dean Koontz tells them he’s worried about the impact on independent bookstores, and James Patterson tells them, “I’m not the endangered species here.”

Meanwhile, a weekend story by Bustillo and Trachtenberg gives an in-depth background to the battle between the giant retailers … and updates the price war: Wal-Mart has lowered prices once more, to $8.99. Amazon hasn’t responded.