Battle Los Angeles

Let us say, hypothetically, that you took all the well-worn cliches of the war genre — especially movies from World War II — and Frankensteined them into one standard War Movie. Then let us say that “Independence Day” had physical relations with that movie. Their offspring (we will pretend that “Independence Day” and War Movie are not both male) would be “Battle Los Angeles,” a sturdy alien-invasion flick that focuses almost exclusively on the military response.

That’s an intriguing angle to take. The scientists, the President, the ordinary citizens, they’re all left out of it. Save their stories for another movie. “Battle Los Angeles” is about a small group of U.S. soldiers, mostly Marines, who stand as the last line of West Coast defense after the other major cities have fallen. If we lose L.A., the country is toast. (You can tell this movie was made by people who live in L.A.)

This combination means that while “Battle Los Angeles” is technically science-fiction, it feels more like a war movie, with its attendant strong-jawed soldiers and dialogue that’s mostly in the form of declarative statements (“Those are unmanned drones!” “They’re following our radio signals!” “It’s a suicide mission!”) and military cliches (“Tell my wife I love her!” “Go on without me!” “I won’t leave you!”). The characters include a staff sergeant (Aaron Eckhart) haunted by the loss of some men under his command in Afghanistan, a brassy female Air Force technical sergeant (Michelle Rodriguez) who “didn’t get this far on [her] good looks,” a scared Marine (Noel Fisher) fresh out of basic training, and so forth. Their backstories and names — both unnecessary, really — are given in cursory scenes before the aliens arrive.

Yet as derivative as all this is — and as much as I’m convinced screenwriter Christopher Bertolini doesn’t realize how derivative it all is — there’s something comforting about seeing the tropes of yesteryear adapted for the age of CGI aliens. This really is like every World War II movie you’ve ever seen, but with frightening extra-terrestrials instead of Germans. (You can argue about which is worse.) It’s like when your grandfather figures out how to use e-mail, but writes every message as if it were an old-fashioned letter. Some things never change, and sometimes that’s nice.

And while the screenplay may be a dialup AOL account, the action and special effects are state-of-the-art. The creature effects are wholly convincing, the destruction and mayhem believable. (And, for once, the movie doesn’t absolutely revel in showing stuff get wrecked.) If you’d told me that Jonathan Liebesman — who made the very bad horror/suspense films “Darkness Falls,” “The Texas Chainsaw Massacre: The Beginning,” and “The Killing Room” — would one day direct a solidly entertaining military procedural about an alien invasion, I would have ridiculed you without mercy. Now you can be the one ridiculing me, for enjoying a tense but unoriginal action flick.

Most of the battle is small in scale: Marines skulking through bombed-out streets, looking for civilians and having occasional firefights with the enemy as they travel a couple “clicks” to the “rendezvous point,” etc. This narrower focus helps — fewer characters means more time spent on each, which increases the chances we’ll be interested in at least one of them. We don’t remember their names, but at least we recognize them as the same people we’ve been with the whole movie.

But the film doesn’t really take advantage of this. While the action is often intense and sometimes rousing, it is still, when all is said and done, just a lot of kids playing war games in the backyard. There isn’t much in the way of humanity or emotions beyond the basics you find in most war movies. This is a good movie that could have been really good if it had tried a little harder to stand on its own without relying on its War Movie DNA.

B (1 hr., 56 min.; PG-13, one F-word, moderate profanity, moderate war-related violence.)