Drew Porterfield and Siobhan Gavagan, of Longview Gallery in Washington, play with a selfie stick in front of “37 Minutes of Miracles,” right, and “Global Perspective, Yellow & Pink.” Most museums allow photography, but those arm extenders for your cellphone camera? Leave them at home. (Bill O'Leary/The Washington Post)

How is it that we ended up with one big idea governing museums, and such a self-destructive one? The museum, we hear ad nauseam, must be a space like any other, must not have its own rules, must not insist upon its own etiquette. The ideal museum, it seems, is seamlessly connected to the ordinary world, is transparent and is easily penetrated by the same signals, currents and fashions that flow through the realms of commerce, entertainment and social connectivity. The museum, as a perfectly democratic space, would have no walls, or laws.

Then came the selfie stick. The device uses a Bluetooth signal to allow people to hold their cellphones at a distance, so as to produce a better-framed image when snapping a “selfie.” Museums across the country are nervous about this new prosthesis for the ubiquitous amateur photographer, and some — including the Smithsonian and New York’s Metropolitan Museum of Art and Museum of Modern Art — have already banned them, just as many prohibit tripods and umbrellas. There was a flurry of stories about the ban on selfie sticks earlier this year, but it felt like a slightly manufactured controversy, with few if any reports of actual damage, and few if any signs of outraged selfie-takers descending on museums with pitchforks and torches.

But the selfie-stick debate is an occasion to think once again about the museum as democratic space. More than 40 years ago, in a mildly misogynistic short story called “Women and Museums,” John Updike described the erotic and intellectual allure of the art museum, and the thrill of its magnificent architecture and the ascent of its “broad stairs leading upward into heaven knows what mansions of expectantly hushed treasure.” The vocabulary belongs to a bygone era of the museum as a sacred secular space: “upward,” “heaven,” “mansions,” “hushed,” “treasure.” The right-thinking modern museum professional would, and perhaps should, contest every one of those loaded associations. The ideal today is a space that is leveling, not elevated; grounded, not heavenly; and without class associations, presumption of quietness, or folderol about treasure.

[Etiquette in the arts: How to behave in the digital age]

Over the past half-century, the democratization of museums led to an unfortunate consequence: Museum leaders are now hypersensitive to any accusation of resisting change or alienating visitors who want cultural institutions to keep pace with the evolution of technology and cultural habits. But the selfie stick was a step too far, and suddenly there was a line in the sand against the relentless march of social-media libertarianism. If the art or other visitors are endangered, that’s where your freedom ends.

The danger to art, however, is only a small part of the selfie-stick problem. There is the nature of the experience as well, and how the selfie changes it. Indeed, it’s not the selfie stick that’s the issue, it’s the selfie — not that anyone will do anything about that.

Most museums now accept that, as long as there are no copyright issues or flashes used, photography does no damage and that to ban it would alienate younger visitors. But the selfie is problematic on multiple levels. Of course it distracts not only the person taking the picture, but also those around him, from the art. But it also extends the cult of celebrity into the museum, because the selfie with a famous painting is essentially doing the same work as a selfie with a famous actor or politician buttonholed by a tourist or fan on the street. It extends the fundamental narcissism of the tourist snapshot — I was there — into something more hostile, an attempt to appropriate the fame of the famous person.

If that seems far-fetched, consider what the selfie stick is meant to do: Improve the image. Without a selfie stick, the subject’s face is almost inevitably distorted, seen too close and with unflattering proximity. The extension of the distance from camera to subject flatters the subject and aestheticizes the resulting image. No longer just proof that you were there, the selfie aims to be an autonomous work of beauty. And the act of taking it no longer just diverts the selfie-taker from the art with which he is supposedly engaged. It also subordinates the art to a new image that strives for its own aesthetic status.

In 1936, Walter Benjamin published his still vital essay “The Work of Art in the Age of Mechanical Reproduction,” which alerted readers to all the ways that reproducing a work of art limits and even destroys what makes it unique, as a particular thing, in a particular place and time, with a history as an object embedded in tradition. He called all the things lost through reproduction the “aura.” The loss of aura still seems, to many readers of the essay, a tremendously sad thing, suggesting a museum full of inert, meaningless, antiquated objects, sealed off from their former powers like superheroes frozen in carbonite.

But of course things are much worse than that. Mechanical reproduction gave way to an era of mass photography, and now to an age in which image-making isn’t just universal, it’s a universally necessary substitute for experience itself.

The selfie stick merely extends what the selfie was already doing: the aggrandizement of the visitor at the expense of the art. After a brief paroxysm of rage, most everyone would be happier if all museums banned not only the selfie stick, but also cellphones and cameras. It would get us back to a place where we could at least recognize and remember the loss that Benjamin noticed almost 80 years ago, and it might define museums as a countercultural space of revolutionary potential, where undistracted thought and un-deflected emotion reemerged as common experience.

But that won’t happen, because the museum must be a space like everywhere else, without boundaries, rules or resistance.

Read our critics’ takes on etiquette in their respective fields:

- Hornaday: Improving manners at the movies

- Sietsema: Hoping to have a good dinner? Be a good diner.

- Kaufman: Dance audiences are too caught up in the performance to be rude

- Pressley: Turn off your phone at the theater. And ignore the prostitute.

- Midgette: How (not) to behave: Manners and the classical music audience

- Richards: How not to be a jerk at a concert