Last month, a young man posting on a Website dubbed "The Urban Prankster Network" (Headquarters for Global Agents of Stealth Comedy!) suggested a novel way to cool off the city of Austin, Texas, when the inevitable hell of a Texas summer bakes streets and fries brains: a city-wide water gun and water balloon war waged by a "flash mob."

It could happen. American "flash mobs" often involve goofy stunts -- the "digital social network" and "cell phone with text-message" age equivalent of 1950s-era collegians cramming sophomores into a phone booth (when phone booths still existed).

A flash mob organizer might send four accomplices a message like this: Paint yourself blue and show up at Sixth and Congress in two hours. In concept, the ability to communicate quickly and virally (think exponents -- each friend contacts four more friends, and those friends four more) quickly multiplies the number of blue-painted crazies unexpectedly crowding a downtown sidewalk.

A couple of years ago, I overheard two mothers discussing a high school party that included a "flash mob-like" activity. A text message provided the insta-mob location. Alas, one of the moms had to drive her son to and from the mob scene. That's an old lesson reinforced: Even improvised anarchy may require parental logistical support.

San Francisco, however, is fed up with flash mobs that leave litter. The San Francisco Chronicle assured its readers that the city's looming crackdown was not "political, ideological or cultural," but a Valentine's Day flash mob pillow fight left heaps of icky, sticky feathers for sanitation workers -- in other words, clean-up costs. The pillow brawl was billed as "the fourth annual," which indicates less flash and more coordination. Unless event organizers take responsibility for the trash, the city may shut the next one down. Here's the bumper sticker: Leave Trash? No Flash.

One hundred seventy-nine years after the publication of his "Democracy in America," French aristocrat and author Alexis de Tocqueville remains the most insightful analyst of American political mores. Tocqueville didn't anticipate flash mob technology, but he understood them in America's context. He noted in volume two of his masterpiece that Americans formed "public associations" for many reasons, including entertainment. Freedom of association flows from the First Amendment's guarantee of freedom of peaceable assembly. Continued...