Continuing the tradition it established with Independence Day, Twentieth Century Fox celebrated this year’s extended July 4 holiday by blowing up a major piece of Washington, DC. It was a nostalgia trip: The demolition of the US Capitol, along with portions of New Jersey, West Virginia and a stretch of Maryland interstate, was Fox’s way of welcoming back Bruce Willis in his role as old-time working-stiff action hero John McClane, in Live Free or Die Hard. (Despite the title, no part of New Hampshire was harmed in making this motion picture.)

A dozen years have passed since Willis last raced around as McClane in Die Hard With a Vengeance–years in which the world saw what real devastation could be visited on an American city, and by men armed only with box cutters. The attack on the World Trade Center ought to have made a relic of McClane, the New York cop who goes mano a mano against terrorists, motherfucker; and if the gravity of events didn’t force this character into retirement, the weight of time on Willis’s body might have finished him off.

But Willis runs his own production company and Fox needed a summer franchise movie, and so McClane, ever resilient, has been pressed back into service. Once more, he commandeers people’s cars, tumbles from high places, fires bullets from an inexhaustible clip and absorbs an infinity of kicks and punches, if mostly from the neck up now, in star-saving close-up; while the still-popular spectacle of destruction has once again been offered to the American people for the pure joy of ka-blooey. Did you need more proof that September 11 did not, in fact, change everything? Then watch our hero of July 4, 2007, take out an Air Force fighter jet–yes, one of ours–using nothing more than his bare hands, an eighteen-wheel semi-trailer rig and a chunk of highway overpass. He’s the box-cutter type himself.

His antagonists, though, continue to have the pretensions of sophisticates. Live Free or Die Hard is the tale of a strike against all the computer systems of the United States, as directed by a manicured white boy who could model for Zegna (Timothy Olyphant) and his equally unemotive girlfriend (Maggie Q), who is Eurasian by background and therefore comes accessorized with a cleavage-baring black jumpsuit and repertory of kung-fu kicks. “I’m in,” these lovers keep murmuring to each other, though without anatomical reference, since the penetration occurs exclusively online. Exemplary creatures of today’s high-priced thrillers, these villains know of no greater excitement than the sight of fingers typing, eyes staring at monitors and progress bars slowly filling. Download 15 percent complete. Download 18 percent complete. Download 17 percent complete. Please wait.

McClane, of course, begs to differ. He has no patience for digital flow, being a guy for whom “technology” is a handy fire extinguisher used for the impromptu incineration of opponents. Somebody halfway sympathetic to the audience needs to help this man. Enter the hacker, Matt Farrell: a surrogate character for all those 18- to 25-year-olds who watch movies for the sake of seeing computer effects. Played by Justin Long, an amiable performer best known for impersonating a Mac computer in TV commercials, Matt is both a plot convenience and a much-needed bridge between younger ticket buyers and Willis’s 40-plus demographic.

As a member of the latter group (and then some), I enjoyed seeing an old guy battle the labor-saving software that now wastes so much of my time. I will also admit that the director (Len Wiseman) did a good job of stimulating my reptilian brain, a part of the body that creationists hold to be merely theoretical. The faithful want me to believe that God must love summer movies, since He designed my nervous system so the frontal lobes could be left idle while the core delights in bursts of pulsing orange fireballs set against an otherwise gun-metal palette. But we must evolve! Thoughts, prompted fitfully and feebly by Wiseman and the screenwriters of record, kept intruding on the sound-and-light show, mostly to comment on the ambiguity of McClane and his nerdy sidekick.

With McClane, the doubleness is familiar. He always mutters about being a tired, put-upon guy whom no one appreciates; but he’s also the first to howl with delight, even before the audience can, when he drops someone down an elevator shaft. If McClane were as plain-spoken as we’re supposed to think, his motto would be, “It’s a dirty job, but somebody’s got to love doing it.” As for reedy, scraggly and bedraggled Matt, I suppose he should have a slogan, too: “When computers are outlawed, only outlaws will have computers.” He enters the story as a cybercriminal, taken into custody by the cop who’s almost a vigilante. By the end, Matt is almost a cop himself.

Live Free or Die Hard is the boot camp that whips this slacker into shape, for the nation’s good and his own. The movie’s terrorists, you see, are homegrown, and they operate by exploiting useful idiots (“as Lenin said”) such as Matt. Witness the danger within: a lax and disaffected young American, self-righteously critical of public servants such as Fox News. (“Don’t you know, it’s all lies, put out there by corporate interests!”) If Matt weren’t carrying important information in his head, McClane might simply beat him to death, as he jocularly suggests doing at one point. Instead, he converts Matt, turning him into someone who respects authority and will take up arms against America’s enemies. Or, to use the precise McClanean terms: Matt grows a bigger set of balls.

Which brings us to the not-so-secret theme.

Imagine today’s inadequate man in a different mode. He still lazes about but in a cheerfully plump way; devotes himself to the computer but without striving for expertise; scoffs at the Man but does so in Los Angeles, where he’s got plenty of company. Take Matt out of an action thriller and put him into a romantic comedy, and he might turn into Ben Stone, the guy with just enough balls to set off the plot of Knocked Up.

A box-office hit and critical success, Knocked Up has elicited commentary both for its sexual candor (in which it was outdone half a century ago by The Miracle of Morgan’s Creek) and for its characters’ decision not to resort to abortion. With all due respect for the political situation in which the film has emerged, I think this latter issue is beside the point. Knocked Up belongs to the genre that Stanley Cavell brilliantly defined as the American comedy of remarriage: films about a woman and man who have separated because their original union was false, and who now must work out a true way to live together. With allowances made for contemporary manners, this is pretty much the project of Knocked Up. There can be no abortion because the drunken one-night stand must lead to nine months of moral, social and emotional education.

But even though Knocked Up respects the conventions of the comedy of remarriage, it also departs from them by taking this deeply adult genre and regressing it toward childhood. Whereas the male lead used to be Clark Gable, Cary Grant or Henry Fonda, today he is Seth Rogen, an actor who is all baby fat and overgrown curls. The basic gag in Knocked Up is that Rogen’s Ben is utterly outclassed by blond, buxom and camera-ready Alison (Katherine Heigl), to whom he can justly say, in drunken wonder, “You’re prettier than me.” The more elaborate gag is that Rogen seems perpetually surprised to have a growly voice and stubbled chin. He belongs in Pampers himself.

Whatever changes Gable and Grant had to undergo in their comedies of remarriage, they didn’t need to learn to accept minimal adult responsibility. You may judge the distance between their era and ours by the fact that Rogen’s education in Knocked Up barely rises to adult topics. He mostly learns to bathe, dress neatly, tidy his room, eat properly, engage people in conversation and read: training for a 6-year-old.

Meanwhile, what process of education does writer-director Judd Apatow propose for Heigl? On the most obvious level, none. She must learn to overlook the unappetizing exterior and love Rogen for the sweet, funny guy within–a task she’s already proved she can accomplish, right at the start, given enough beer and tequila. This leaves her seeming unformed (embryonic, you might say) compared with predecessors such as Barbara Stanwyck and Irene Dunne–though more from Apatow’s negligence than from any design. And yet Heigl, too, faces a subtler challenge (subtler, because it is relatively unexplored in the script): to break her dependence on an older sister with whom she lives as a semi-official boarder, sharing in her sister’s family life while observing the unhappiness of her marriage.

If Cavell were to interpret Knocked Up, maybe he’d seize on Alison’s deeper problem and identify the movie’s essential question as one of community. What is the right relationship between a married couple and the people around them? The initial union of Alison and Ben is false because the characters won’t budge from their existing groups. (His buddies keep him juvenile. Her sister and brother-in-law keep her mesmerized by domestic pain.) If Alison and Ben are to choose each other, rather than be joined by circumstance, they must therefore peel themselves away from these others, not so completely as to be disloyal but enough to form the beginning of a semi-autonomous community of their own–which is Knocked Up‘s definition of a true marriage.

Fine with me–even though, for all the cinema I saw in Knocked Up, I could just as well have been watching television. I chuckled some; I smiled a lot. And this community business reassured me. “What if the peer-group standards in Knocked Up are plausible?” I thought. (And why wouldn’t they be, with the gross now mounting above $100 million?) It would mean that while a large number of American men enjoy watching John McClane’s rampages, they expect one another to be no more testosterone-charged than Matt the Hacker.

Very reasonable, I say–because in a decent community, men ought to nerve themselves up before getting into fights. On September 11, on United Flight 93, the men who really did go mano a mano against terrorists weren’t professional heroes, ready to do violence at any time. They were a toy company manager, a public-relations flack, a couple of salesmen and a guy who worked for a software company. They might just as well have been Ben and Matt from Knocked Up and Live Free or Die Hard, each of whom spends an entire movie getting ready to assert himself.

Live Free or Die Hard is knowing enough to admit this reality, when in the end it proposes its own little comedy of misalliance, between Matt and McClane’s daughter. Having survived the obligatory hostage ordeal, she has rediscovered her affection for the old paternal bully and is deeply grateful to him; but compared with Matt, she knows, Dad’s a dinosaur.

The good news: If young Ms. McClane shares the apparent peer-group standards of women in today’s movies, perhaps we may look forward to Bringing Baby Up Hard.