NEW YORK – I think it is fair to say that the shark has been permanently displaced by the dog.

When scriptwriters have run out of mustard, the show hasn’t “jumped the shark,” as we’ve been saying since the Fonz literally jumped a shark while water-skiing. These days, the political show has eaten the dog.

Yes, it has come to this.

It’s the most pivotal presidential race in human history , and we’re debating which candidate cares most about dogs. I did my best in a previous column to illustrate the silliness of the Obama campaign’s focus on a 30-year-old Romney/dog travel episode, but, alas, I misjudged our capacity for the absurd.

As I was hitting “send,” the Romney campaign was touting an anecdote from Barack Obama’s memoir in which he mentions having once consumed dog meat. (Confession: I only scanned the memoir and failed to seek out “dog eating” in the index.)

Rarely do I return so soon to a topic, but the zeitgeist is a persistent nag, and the volume of my mail suggests that this story has become more than a political metaphor. Not to overstate, but it has become a measure of our national sanity. Things are not looking good, my friends.

Republicans were so gleeful to have found a worse dog story about Obama that they have lashed out with Kujoesque rabidity. Sure, Romney may have carted his dog Seamus in a crate strapped to the roof of his car, but Obama ate dog!

“So there, Ms. Parker. Why didn’t you mention that in your little column, you (female canine)!”

Even a close friend, who usually can be relied upon to tackle complex issues with calm, intellectual reserve, emailed: “I guess it’s better to eat your dog!”

Are we really arguing about whether eating a dog is worse than putting one in a kennel?

The thought of eating man’s best friend is, of course, repulsive to us – as it is, no doubt, to Obama.

One does wonder, however, what the rest of the world must think of us? Is this what happens to old democracies? Are we too silly to be taken seriously anymore? A rock star is revered for ranting about guns; Secret Service agents on presidential detail allegedly hire and then try to cheat prostitutes; and presidential candidates run on their canine histories.

If we look ridiculous to the rest of the world, and surely we do, why don’t we look ridiculous to ourselves? Now there is a question worth pondering.

We seem to have come unhinged, as well as inured to offense.

As to how we’ve gone to the dogs, the answer is familiar. Humans like spectacle, and Americans in particular prefer humor to malaise. For the latter, we can be grateful.

On the whole, however, this Bo vs. Seamus debate is a luxury of full stomachs. That we tend to anthropomorphize animals is an understatement given that Americans spend about $50 billion a year on their family pets. Thus, eating a dog is viewed as tantamount to cannibalization. Installing a dog in a crate for 12 hours atop a speeding car may as well be child abuse.

The endless presidential campaign hasn’t only taken a toll on the candidates, it has exhausted a nation. Dog-tired of chatter, spin and politics, we’re all too happy to avert our gaze from the inconceivable to the insignificant.

As narratives go, we have eaten the dog.

Kathleen Parker’s email addressis kathleenparker@washpost.com.