Can something as rarified as haute couture be political? Or, more to the point, can something as innocuous as a fashion exhibit do double duty as propaganda?

After seeing a small but potent collection of dresses from the 1940s at the Fashion Institute of Technology – an exhibit that originated at the Kennedy Center for the Performing Arts in Washington, D.C.- you may be tempted to answer both questions with an emphatic “yes.”

“Fabulous! Fashions of the 1940s,” the misleading title of this show, which runs through July 30, is less an examination of glamour, fabrics, and cut than a story of two nations – one scrappy, one august – dueling for creative supremacy against the backdrop of a major world crisis.

From the 1600s through the 1930s, Paris reigned as the capital of fashion. American swells traveled to Paris for their clothes and those who couldn’t afford the trip would wait for Seventh Avenue to churn out copies of Parisian innovations from the likes of Vionnet, Madame Gres, and Balenciaga.

But with the Nazi invasion of Paris in 1940, the French-American fashion traffic halted and American designers were forced to rely on their own resources instead of taking cues from the continent.

In the process, America concluded: Who needs the French? American designers such as Claire McCardell, Adrian, and Norman Norell (who is strangely missing from F.I.T.’s exhibit, although he’s mentioned in the press notes) proved capable of creating exciting fashion without old-world guidance, even in the face of wartime rationing. These designers developed a new silhouette that would come to define the 1940s.Think of Katherine Hepburn in “Woman of the Year” or Lauren Bacall on the cover of Harper’s Bazaar.

Out were Balenciaga’s hip-accentuating court-style gowns; in were sharp-shouldered suits reminiscent of men’s tailoring, belted at the waist and constructed of sensible fabrics like wool and cotton. To conserve fabric, long, full skirts were replaced (by government mandate) with sharp pencil skirts – which experienced a smart revival last season.

The entrance of women into the workforce – and their need for clothing that wouldn’t interfere with their duties – was, of course, a major influence on these styles. The soigne styles of Mainbocher had no place in the boardroom, to say nothing of the assembly line. In fact, the American-born, Paris-based couturier returned to New York at the onset of the war and ended up designing uniforms for Women Accepted for Volunteer Emergency Service, the American Red Cross, and the Girl Scouts.

But the real triumph of American fashion in the 1940s belonged to female designers such as Claire McCardell, who, much like Chanel before her, made her lack of access to luxury fabrics a virtue. With her designs for simple, short-legged jumpers and bathing suits in simple fabrics such as gray wool and khaki cotton, McCardell gave birth to the modern American sportswear movement.

In 1944, after Paris had been liberated, reports surfaced that some French couturiers had continued working during the occupation, producing extravagant confections for wealthy collaborators and Nazi dignitaries. That same year, the American War Production Board accused the French of “flagrant violation of the imposed wartime silhouette.”

Still, Americans couldn’t resist the temptation of Parisian decadence for long. In 1947, Christian Dior introduced his famous “New Look,” a reaction against wartime austerity that employed yards and yards of luxurious fabric in long, full-bodied skirts. (Strangely, F.I.T. offers no example of Dior’s handiwork, only an American copy; it would have been fascinating to compare the two.) The war between New York and Paris as the world’s capital of fashion continues.

Fittingly, the emergence of the New York fashion industry also saw the birth of the Fashion Institute of Technology itself, which opened its doors in 1944.”Fabulous! Fashions of the 1940s” is F.I.T.’s 60th birthday present to itself, commemorating a time when the now booming American sportswear industry was just finding its reason for being.

“Fabulous! Fashions of the 1940s,” through July 30 at the Museum at FIT, Seventh Avenue at 27th Street, www.fitnyc.edu/museum.