Our national obsession with celebrities — figures we recognize from TV and film and, in some cases, just for being famous — has for many years sold magazines and influenced such art forms as popular music. But the fascination with celebrities is now having an impact on American theater, from Broadway to summer stages, where film and television stars with little or no stage experience are being brought in simply to sell tickets.

The commercial theater has always had stars pulling in audiences. There’s nothing new about that. But the stars of the past were generally stars of the theater: Mary Martin, Carol Channing, Alfred Lunt, Ethel Merman — people whose reputations were solidly rooted in the stage performance. That, sadly, is no longer true.

Today, to get the degree of star power offered by past Broadway celebrities, producers feel forced to mine Hollywood for names that a general audience will recognize and come to see. In some cases, these performers have been trained in the theater and have moved to film, some of them regularly going back and forth (Kevin Spacey, for example). Others are making not only their Broadway debut but their stage debut — these screen stars are arguably the most sought after, because their fame is the greatest, resulting in monumental box-office sales.

Theaters everywhere face the same problem: bringing in a new, younger audience. The average age of theatergoers is quite old (look at any indoor or outdoor production this summer); as these audiences die out, they are not being replaced by younger people. No wonder theater producers will do anything short of Dish Night to bring people in.

However, bringing in performers who offer nothing but fame is not helping the situation. At best it’s a short-term solution.

The hope is that people attending a play because of a big name will enjoy the theater experience so much that they will return, again and again, with or without a star attached. But if the star is not up to the task at hand, the theater experience is cheapened, and you are probably not building an audience. People who have seen less-than-satisfying productions with untalented celebrities can hardly be blamed for not going to plays.

Yet theater producers — instead of picking a play and then casting it with the best performers _ are picking celebrities and then looking for the play. Why aren’t they looking for new writers, directors, and designers, with new ideas that would attract a younger audience — who now would rather stay home with their Play Stations and 5,000 cable channels? Tobacco companies do a much better job addicting young smokers than the theater does recruiting young theatergoers. The cigarette makers learned long ago to hook people when they’re young and have them for life; the theater would do well to follow this example (and it needn’t kill the people it hooks).

The theater provides a unique personal experience. If you make and market that experience as being relevant to the lives of young people — if you put it on their radar screens — they will come, and they will keep coming. And if a famous name can help that cause, then by all means get his or her agent on the phone. But please make sure that the famous person brings more than celebrity to the first rehearsal. If the star’s only stage experience is playing the third tulip from the left in the grade-school salute to spring, please, I beg you, think twice about casting this person.

There have certainly been plenty of incredible star-driven theater productions in recent years, including “Long Day’s Journey Into Night” with Vanessa Redgrave and “Annie, Get Your Gun” with Reba McIntyre. Some of these stars have had much experience in the theater; others are just getting their feet wet. But without exception they’ve made “the play the thing,” and not their own stardom. They’ve worked hard to serve the theater, not themselves.

Celebrity casting is not wrong; it has simply gotten out of hand. Now anyone with a high Q rating is fair game for Broadway stardom, regardless of acting ability. If you’ve made The New York Post’s Page Six for throwing phones at hotel clerks, you’ve probably got producers banging down your door.

Theater’s mission is to tell stories that people want to hear or need to hear or are yearning to hear — to hold a mirror up to nature. But the more theater chips away at this mission, the more it becomes just another opportunity to worship at the celebrity altar. Then, a stage production, like an issue of People magazine, is to be glanced at and forgotten.

Robert Boles is the director of the theater program at the University of New Haven.