The other day I caught myself in another post-apocalyptic reverie, where widespread death and panic — via alien invasion or any other of pop culture’s preferred narratives of ultimate catastrophe — offer a strangely relaxing balm to life’s everyday anxieties.

What would happen if a virus claimed 100 million or more of My Fellow Americans? After the chaos, what would remain for the rest of us? What gold-based economy could we cobble together? What becomes of the suburbs?

Notice I use the words “we” and “us.” Because what fun is a doomsday if you’re not one of the scrappy, well-armed survivors? That’s the true narcissism at work in almost all space-invader, mass-epidemic, zombie-infected, climatological hunger games: Me and mine, we get through, but just barely. You and yours? Not so much.

Which brings us to yet another dystopian vision with Steven Spielberg’s brand name affixed to it (as executive producer), this time as a cheap-looking but occasionally intriguing sci-fi social study called “Falling Skies,” which premieres Sunday night on TNT.

Aliens have stood in for a lot of metaphorical worry stones over the last century — they’ve represented emigration and immigration concerns, fascism fears, the Red Menace and deadly pandemic.

Now it seems that extraterrestrial hostility triggers in the American character a fierce defense of family, currently on display in “Falling Skies” but also a strong theme in the Spielberg-influenced “Super 8” down at the multiplex. As with Spielberg’s memorable “War of the Worlds” remake in 2005, these stories are no longer about uniting the broader family of man against a common enemy. They’re about the more self-interested impulse to protect one’s family unit.

Though well-armed and edgy, “Falling Skies” is subliminally preoccupied with helicopter parenting and the idea that my child is more gifted than yours, and thus more worthy of salvation. A band of freedom fighters survives on wits and what appears to be an ample supply of Dinty Moore stew, but it feels like they’re all still using the same tactics honed in seeking to improve their kids’ test scores and chances at the now-obliterated Ivy League.

As seen in “Independence Day,” “District 9” and both the old and new versions of “V,” aliens arrive and squat their monstrous motherships over only those cities large enough to have major league sports franchises. In “Falling Skies,” this has meant curtains for Boston, where a scant number of survivors have formed units of militias-on-the-go, operating without radio contact or an apparent central command. It’s the tea party’s wildest dream come true.

As part of the testy 2nd Mass unit, Noah Wyle is Tom Mason, the widowed father of three sons. He used to be a college history professor (read: soft, ivory tower, liberal). Now, six months after the alien takeover, he’s a work in progress as a machine-gun toting soldier (read: “Red Dawn,” true patriot, alpha dad).

The aliens, nicknamed “Skitters” by the human freedom fighters, dish out destruction and death in the usual H.G. Wells manner of no-manners, all but ending the cushy lifestyle the Americans once knew. Remorse is an essential thread in the mood of “Falling Skies” — a moralizing tone of all space-invasion epics now; enjoy today and what you have, for tomorrow it could all belong to reptiles from space.

What’s more, the Skitters want to enslave our children. They are fond of nabbing teenagers and affixing a biomechanical centipede-like “harness” to their spines, which turns the kids into mute, obedient servants. (Insert your own lazy teenagers/texting joke here.)

Sure enough, Tom’s middle son, Ben (Connor Jessup), a likeable mathlete, has been captured by the Skitters. His oldest son, Hal (Drew Roy), a strong-willed lacrosse jock, has taken quite well to the soldiering life, while his youngest son, Matt (Maxim Knight), understandably pines for the olden days of PlayStation and breakfast cereal.

The now-lobotomized alien slave Ben is spotted marching in the Skitter army; Tom’s unyielding desire to rescue him — indeed, his instinctive need to put family ahead of the larger group — runs counter to orders of the 2nd Mass’s leader, Capt. Weaver (Will Patton). During a Skitter skirmish, another father discovers his harnessed son and brings him back to base camp. You think teenagers are moody now? Try removing the alien contraptions welded to their spines.

Meanwhile, Tom and the captain’s arguments about the good of the community vs. the needs of the individual serve as a flimsy recurring theme in “Falling Skies” and quickly grow stale.

Like AMC’s uneven zombie drama “The Walking Dead,” “Falling Skies” makes up for its special-effects budget deficit by preoccupying itself with a lot of hack sociology, in which various character archetypes express themselves in us-vs.-them cliches. The writing and acting tend toward scenes and lines we’ve heard in countless, failed sci-fi TV series — a form of plagiarism that fans of the genre more kindly regard as homage.

This is one of those action dramas that I call a “thanks for what did you back there.” That’s when characters whose personalities clash must face the slimy, invincible enemy together and then bond in combat. This inevitably leads to one character begrudgingly offering his gratitude to his former adversary: Thanks for what you did back there.

At survival camp, Wyle’s Tom is engaged in the romantic version of “thanks for what you did back there” with Dr. Anne Glass, a tough pediatrician (Moon Bloodgood) who serves as the 2nd Mass’s doctor, keeping private about her emotional wounds.

When Tom’s strike team runs afoul of a band of survivalist marauders squatting in a high school auditorium, they are captured by the gang leader, John Pope (Colin Cunningham), who turns out to be the series’ most compelling character. This happens not a moment too soon, since the show is slowed by so many wooden performances, Wyle’s included.

As it ambles along in the first six episodes, you begin to root for the aliens, which cannot have been the writers’ intent. When the freedom fighters infiltrate an alien nest at the ruins of a hospital, viewers will see the unsettling image of a Skitter lovingly napping with her litter of human teenagers, stroking their heads with something like love. Everyone looks content. Did the aliens come to save us from ourselves?

This is perhaps the most intriguing and regrettably unexamined possibility presented in the first half of the “Falling Skies” season — that someone (some thing) could come along, destroy your family and property values, and then take better care of your children than you did.

I’d watch a show about that, but in more scenes than not, “Falling Skies” employs the same old space-invasion hokum. There is too much empty bravado, clumsy post-American (earthling) patriotism, and a lot of scruffy dudes and shapely dames all thanking one another, for what they did back there.

Falling Skies

(two hours) premieres

at 9 p.m. Sunday on TNT.