T om Hanks was once an actor, a rather good one, before he became no mere star, but a Hugely Important Personage, akin to a grand vizier.

Now, whatever he touches or does, becomes Terribly Monumental so that an entire nation, even a planet, will realize that space exploration equals macho goodness; or World War II equals worth remembering; or his new hair equals weirdly colossal.

I fault Forrest Gump for this.

Then again, I fault Forrest Gump for everything.

Hanks works with Consequential Auteurs such as Lord Steven Spielberg and Archduke Ron Howard, gifted directors who have grown self-important and aggrandizing while accessing the common touch through baseball caps, beards and, despite vertiginous tax brackets, persistent frumpery.

Incidentally, Howard is an executive producer of “24,” starring Kiefer Sutherland as Monstrously Intense agent Jack Bauer who talks consistently in the same low voice as if he’s a millisecond away from a heart attack, though he has the world’s best cell phone service, and computer whiz Chloe O’Brian always has his back. (We’ve taken to talking like Jack around our house. To wit: “Mom, as a matter of national security, you need to intercept the jam on the table.”)

This brings us to “The Da Vinci Code,” which opens this week, directed by Howard and starring Hanks and his weirdly colossal new hair. The movie is based on Dan Brown’s book, so Cosmologically Symbolic that it is a requisite feature of every nightstand in America.

At 40 million copies worldwide, it’s the literary equivalent of the Happy Meal. Except it’s not making everyone happy.

“TDVC,” like all things supremely successful, has become bigger than itself. Da Vinci’s “Mona Lisa,” which graces the cover and launches the story, seems beside the point. It’s a masterpiece only in service to the story.

The book has spawned a lawsuit, heated debates and many ponderous Web sites, while solidifying Brown’s importance, to say nothing of his entrenched sartorial uniform of turtleneck and tweed.

As it deals with the Roman Catholic Church and sex, specifically with the notion that Jesus canoodled with Mary Magdalene, “TDVC” has launched a thousand radio and cable conversations and considerable outrage by scholars and clerics. A papal official has urged Catholics to “boycott” the movie.

Like they needed help selling more tickets. Louis B. Mayer must be kvelling in his grave. You can’t buy publicity like this.

Assuming “TDVC” is gospel is like confusing “Gone With the Wind” with Grant’s memoirs.

Brown’s book also contains a super-secret powerful Catholic order that acts as if it were run by Tony Soprano, that is, if Tony could manage his crew better and take it global. Mix the Catholic Church with Jesus becoming a father, add a moblike religious organization, and you’ve got a trifecta of controversy.

“The Da Vinci Code,” people tend to forget – including, at times, Brown in his turtleneck and tweed – is a work of fiction. It’s a page-turner, not history. It’s entertaining. To many readers, it’s fun.

That is not the same thing as Hugely Important.

With Hanks and Howard involved, the movie has intimations of transforming a beach book about Opus Dei into a Major Opus. The whole project smells of serious art, when what it should smell of is buttered popcorn.

We don’t need self-important artistes trying to turn folderol into gravitas. When I heard about Hanks and Howard, my already-heavy heart sank. Weren’t the Coen Brothers and Owen Wilson available?

We need more fun. We need to understand that some stuff is merely entertainment and not Terribly Important. Even in this day and age, it isn’t necessary to get all Jack Bauer about everything.