The physical design of telephones has made the hangup impossible for the would-be hanger-up as well. The model 500 series telephone supports hangups as a function of its physical form. It comes in two parts, base and handset, offering something to hang up and something to hang it upon. Flip-style mobile phones were the last devices to offer a physical equivalent, the crisp, satisfying snap of the closing shell offering a reasonable parallel to the handset and hook.

Hanging up on someone is a physical act, a violent one even, one that produces its own pleasure by discharging acrimony. Like the model 500, the flip-phone supports hang ups because its form is capable of resisting them; because it can survive the force a hangup delivers. Just try to hang up your iPhone or your Samsung Galaxy. I don't mean just ending a call, but hanging up for real, as if you meant it. For a moment you might consider throwing the handset against a wall before remembering that you shelled out three, four, five hundred dollars or more for the device, a thing you cradle in a cozy as if it were a kitten or a newborn.

Everyone is a milquetoast when a smartphone is in their hand. Relenting, you might slide it across a table or a counter to signal your distress -- with a necessary gentleness that belies true disgust.

By contrast, the model 500 handset acted as a proxy, a voodoo doll for your interlocutor as much as an audio route. The mobile handset is different: an extension of the self rather than an implement. To do violence to it amounts to self-harm rather than catharsis. In fact, it's barely possible even to hangup mobile calls in the ordinary sense, after their natural completion in typical circumstances. The solid handset of the Bell era may remain imprinted upon smartphone displays or buttons as skeuomorphic icons, but the device itself invites you simply to "end" the call, like one might end high tea. And even that isn't necessary. Unlike a conventional switched line, a mobile device won't remain on the grid absent a live connection. After a call, it's not uncommon simply to stow a smartphone without further interaction and wait for the other party's disconnection to terminate the call.

Lamenting the demise of hangups offers little more than crass nostalgia for an admittedly weird, anonymous aggression. It's pointless wistfulness, too, since the phone call itself has become an endangered species. Today we have replaced synchronous communication methods with asynchronous ones: email, text message, even instant messaging are means of dispatch for which reply is never guaranteed, nor perhaps even expected. Where the analog telephone sampled the voice of its callers as they spoke, computer and smartphone communication systems sample larger temporal swaths of social behavior.

Today, we've traded in our hangups for our hang-ups. The social disruption we now give or get via mobile devices is not the belligerence of hanging up or having been hung up on, but the neurosis of not having received a response. In place of the threat of disengagement in fixed-line switched analog telephony, we find a subtly different fear in cellular telephony and its digital cousins: that of disregard. In the past the telephone was most threatening when it cut someone off; today it its greatest menace is to reveal that you were never really connected in the first place.

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