So, just what is it with zombies?

You can’t turn on the TV or see a movie without coming across a pack of shambling, drooling figures of all ages and backgrounds, their features eaten away by decomposition, lusting to drag people down and eat their brains.

And that doesn’t even count the Occupy movement.

Today is opening day for what may be the first real undead epic, a Brad Pitt zombiepalooza called “World War Z,” based on a novel depicting an ultimately successful conflict to overcome a global epidemic of zombieism. Or zombiemania. Or whatever.

No matter: They’re mad, they’re bad, they’re dead, they’re famished, and they’re everywhere.

I can’t help thinking that there’s something under the skin (decayed, slimy and flapping loosely as it is) of the zombie craze. Nothing becomes this popular without standing in for something else, and zombies are ubiquitous.

True, other supernatural creatures aren’t shortchanged — we’re constantly seeing new iterations of ghosts, werewolves, vampires and mummies — but zombies seem to have a special niche in the modern imagination.

Wikipedia lists 641 movies with zombie characters, including “Z: A Zombie Musical,” “Working Stiffs,” “Teenage Zombie House Massacre” and my favorite, “Attack of the Vegan Zombies.” Hope you didn’t want your salad with tomatoes.

That roster includes George Romero’s ground-breaking (so to speak) five-film “Dead” series beginning with 1968’s “Night of the Living Dead,” TV shows like “The Walking Dead,” novels such as “I Am Legend” and comic books (er, “graphic novels”) of all of the above.

Historians of the genre (yes, they exist) say the zombie legend began in Haiti, where sorcerers allegedly could reanimate the bodies of the recently departed to use them as slaves — but those creatures didn’t display any independent acts or brain-eating habits of their own.

The 1932 movie “White Zombie” is said to be the first film in the genre, but the concept took off with a number of films made from the previously mentioned “I Am Legend,” a 1954 classic by science-fiction author Richard Matheson that has spawned four movies starring the likes of Vincent Price, Charlton Heston and Will Smith.

But none of that answers the “Why zombies?” question. A few writers have speculated about the symbolism of the genre, with one, Walter Hudson, claiming on May 19 on the PJ Media website that zombies provide a way to work off aggressions, in the style of a first-person-shooter video game.

“Zombies provide guilt-free slaughter. No one feels bad about shooting something that’s already dead. … Zombies are amoral. They have no agenda, no emotional motivation, no pain. They simply menace. So putting them down represents no moral dilemma.”

Still, they can “also serve an adaptive purpose in storytelling.” For Romero, Hudson says, they implied a fulfillment for biblical revelation, bringing “the wrath of God” on a corrupt system, a consumer culture that denies any meaning or purpose to life.

And if that is true — Hudson thinks society is better than that — the idea of zombies still allows those who are bored and purposeless to envision a future in which intelligence, resourcefulness and adaptability are the keys to survival.

Thus, fans of zombie stories boost their egos by being encouraged to think they would be among the few survivors, enduring on the basis of their unique skills and traits.

Social commentator Mark Steyn also took a whimsical look at zombies in “Undead Reckoning,” an April 24 column on National Review Online. He quotes writer Amy Wilentz of The New York Times, who sees them as “the unquestioning workhorses of global capitalism,” who “work free and never go on strike.”

That’s too simple, Steyn says: “The zombie doesn’t seem to work at all, but rather feasts on the functioning members of society, in turn zombifying them.”

He says it is instead America’s bureaucrats and other “governing institutions of the West (who) seem to have internalized and accepted zombie psychology, staggering on like glassy-eyed cadavers frenziedly hunting down the last remaining non-infected — the ‘1 percent,’ to coin a phrase — on which to feast.”

In fact, the entire Western world itself “is largely a collection of zombie nations — Greece’s rotting fingers reaching up out of the grave to wrap its decomposing flesh around the ankles of Cyprus and Germany and beyond.”

Sounds plausible to me. But still, something’s lacking.

For there to be a genuine real-world referent for zombies, there would have to be an actual group that is willing to attack men, women and children randomly and without mercy; not appear to fear death; have a worldwide reach; be able to acquire new members on a regular basis; and keep on pursuing its victims no matter how many of its members were killed or restrained.

Hmm. Can anybody think of a group like that?

M.D. Harmon, a retired journalist and military officer, is a free-lance writer and speaker. He can be contacted at:

mdharmoncol@yahoo.com