Four years ago, Facebook was the sunny side of American life.

It was Christmas cards and thank-you notes. It was Parents Night at the elementary school. It was the country club dining room, where you greet Mr. and Mrs. Bruskin with a warm how've you been. It was not, yet, the valet stand, where you wonder aloud how she stands his drinking and your husband answers without caring who else hears, "She eats."

These days, as I've noted, people are tired of being nice on Facebook. Or maybe they're tired of being nice in their own homes. And they must be tired of shouting at Rachel Maddow and Sean Hannity. So increasingly, they're calling each other out—on racism, on naivete, on Chick-fil-A—on Facebook.

And as the presidential election approaches, I'm afraid Facebook is about to feel more like the American Civil War: Friends fighting friends based less on their self-interest than on tribal feelings connected to mysterious myths in their minds, under the influence of economic powers they do not fully know—and for imagined glory that will almost certainly elude them all. And in the end, leaving bad scars.

As the election approaches, I'm feeling the old familiar anger and the righteousness rising up inside myself (as you may have noticed).

And I'm seeing it begin to rise up in others, just as it did in 2008. But this election year offers none of the poetic sense of possibility that some of us felt last time …

… and so it promises to be just as bitter and only more grim, as neither side is excited about winning but each is terrified of how they'll feel if they lose.

So this time, it won't just be the professional and volunteer soldiers fighting on the faraway battlefields of their newspaper columns and politcal blogs. It'll be all of us, fighting hand-to-hand without any training or rules—in our kitchens with steak knives, in our bedrooms with reading lamps, in our bathrooms with shit.

On Facebook, with words.

23,000 Americans died at the Battle of Antietam. You don't think this election will cost Facebook Nation at least that many Friends on both sides?

It's not a call for peace that I'm issuing here. It's a warning to people who want no part of the fighting, to find shelter—and forget your Facebook password.