BALTIMORE, MD, MAY 17, 2012: School children unfold a 30-by-42-foot American flag at Fort McHenry. (Astrid Riecken/FOR THE WASHINGTON POST)

Kate Cohen is a writer who lives in Albany, N.Y.

We were in it for the boat ride. Baltimore was hot by 9 a.m., and across the harbor, Fort McHenry beckoned. I knew it had something to do with the War of 1812 and “The Star-Spangled Banner”; I even knew (from the fort’s Web site) that September would mark the anthem’s bicentennial, and that celebrations were underway. But honestly I didn’t care: I have no interest in military history, and I’m not patriotic. My personality is less “my country right or wrong” and more “let’s look at the other point of view.”

So I was unmoved when we docked at Fort McHenry National Monument and Historic Shrine. And I opened the door of the visitor center warily, like an atheist heading into church. Instantly, cold air enveloped my sweaty skin, tempting me to convert. Ah, the good old U.S. of Air-conditioning. Even my children opted not to tour the sun-baked garrison just yet but rather to stay inside and read a bit of history first.

The wall text in the exhibit off the lobby was impressively balanced; I read the arguments for and against declaring war on Britain in 1812. I decided I probably would have been against it, suspecting hawkish congressmen of being beholden to warmongering shipbuilders and cotton growers. I tried to picture myself in 19th-century garb, railing against the naval-agrarian complex.

Then the lights dimmed.

Movies in museums, no matter how bad, are always a relief. Nobody admits it, but everybody loves the chance to sit for a moment and stop thinking.

Which is precisely what this 10-minute “orientation film” intended. No “other point of view” here. The British invade, maraud and terrorize: “Up and down the Chesapeake Bay they raided, destroying towns and farms and spreading fear,” intones the deep-voiced narrator. The Americans — terrified “citizen soldiers” — frantically dig trenches and wait “with bated breath.” The soundtrack thrums with drums, horns and the whistle of cannonballs. Their bombardment is “ferocious.” Our return fire is “desperate.”

Oh, sure, we’re the ones who declared war, and didn’t we invade Canada the year before? But this movie studiously avoids complexity. This is the kind of movie in which the voice-over informs us that citizens prepared to flee and then a re-enactor in a top hat shouts, “Citizens, prepare to flee!” and then we watch while . . . citizens prepare to flee. Then Top Hat adds something like, “And take your valuables!” and a distraught citizen, rushing to pack his cart, trips and drops the family silver.

Nothing subtle about the execution — or the point. Want to fire up a little patriotism? Dwell on the sense of threat, on the idea of America — Americans — under attack. I am lucky enough to have experienced that threat only rarely, and only briefly. But maybe in 1814, I would have feared for my young country and for my family. Maybe I would have voted for the war.

I know, I know: No voting for me until the next century! Still, I tried to imagine how it would feel to live in an underdog country. I tried to imagine how it would feel not to know whether America would prevail, or even survive.

In the movie, mud-splattered citizen-soldiers fight on. “But would it be enough?” the narrator frets, as Francis Scott Key peers anxiously through his spyglass.

“A huge flag was raised above the fort. But whose . . . ?”

And all of a sudden — even as I chuckled at the canned suspense — it hit me: the simple brilliance of “The Star Spangled Banner.” Why a hard-to-sing memento of a minor war succeeds as our national anthem. When you think of it as an earnest expression of anxiety, when you hear the plaintive questions behind the flowery language — Can you see the flag? Is the flag still waving? — it becomes deeply moving. To be on the verge of losing something is to realize how precious it is. And, in the song, the urgent question isn’t even answered. It just hangs there, a crystallized moment of panic and hope and love of country.

Nobody sings it that way. Certainly not in the movie. Once Key espies the broad stripes and bright stars and his friend exclaims (I’m not kidding), “Huzzah!” we get a men’s choir in full, triumphant voice. Then a shot of the flag in the clearing smoke. And then, as the song reaches its climax, the movie screen rises and the room fills with light and we are looking through plate-glass windows to the outside, at our flag, in real life, against a blue and white summer sky.

Is the flag still waving? It is. And I have to clear the lump in my throat before I can say, “Hey, kids. Let’s go out and take a look around.”