Supporters swarmed the State House on Wednesday to urge lawmakers to oppose a bill sponsored by Rep. Steve D’Amico to cap the film tax credit. The industry is showing itself to be a bigger force than it was in 2005, when lawmakers first adopted the credits. That’s because the credits are working, and there are plenty of local companies that have been adding many year-round jobs during the worst depths of the recession. D’Amico once told me he hoped that the movie studios that are proposed for Massachusetts would never get built. His reasoning is that such large complexes would create a critical mass of permanent film industry workers in the state, making it politically impossible to take the tax credits away. State lawmakers are finding out that the critical mass is already here. The leaders on Beacon Hill will now need to decide if they want to chase it away.

Hollywood history buff Tom Hanks made a Splash at the JFK Library last night at a screening of his latest World War II epic titled “The Pacific.”

The crowd of more than 300 in the capitol’s largest hearing venue was overwhelmingly in favor of the current tax credits.

“You can’t opt in and then out of offering film tax credits,” said producer David Hoberman (“The Fighter” and “The Proposal”) referring to Gov. Deval Patrick’s plan to cap the film tax credit at $50 million – down from around $125 million. “If you’re going to stay in the business of making movies, then stay in the business,” said the man behind Disney’s Mandeville Films, who was at Suffolk University yesterday leading a screenwriting workshop for 50 undergrads. “You need to develop infrastructure and talent. It takes time for people to feel secure enough to stay in Massachusetts if they know there’s going to be work,” he said.

Martin Scorsese’s suspense thriller, “Shutter Island,” led the North American box office for a second consecutive weekend on Sunday, fending off strong debuts from the comedy “Cop Out” and horror remake “The Crazies.” Leonardo DiCaprio, who has collaborated previously with Scorsese, stars in the picture as a federal marshal stranded at a prison hospital for the criminally insane off the coast of Massachusetts in 1954.

If Professors Fitzgerald and Enrich stepped out of their offices at Northeastern University and sauntered to where wage earners are struggling to meet mortgage payments, they might reassess the value of “transient’’ jobs. In Dorchester and South Boston during the summer production season, on the set of the “The Zookeeper,’’ just one of the movies then in production, they would have seen many employees who were happy with their transient union jobs. At the Franklin Park Zoo set, where I worked, there were more than 100 employees for a number of months. They included carpenters, plasterers, painters, greenspersons, Teamsters, dressers, electricians, and laborers, many who had been laid off from other industries.

Joe Maiella, president of the Massachusetts Production Coalition, an unexpected attendee at a State House briefing held by critics of film industry tax breaks, took on the leading opponent, Rep. Steve D’Amico, challenging his facts and offering his version of “what’s true” about film production credits.

Word outta Tinseltown is that the Cambridge homey will star as Robert F. Kennedy in a biopic about the slain senator.

The Dennis Lehane novel on which “Shutter Island” is based takes place in Massachusetts, and the film was shot almost entirely in the Bay State. “We looked at Massachusetts, Connecticut and Rhode Island — searching for incentives so we would get a bang for the buck,” says location manager Robin Citrin. “Massachusetts had good ones, plus a lot of abandoned mental hospitals, some of them with incredible architecture.”

This film presence can offer a myriad of options to VES graduates like Horovitz who decide to remain in the area. Upon graduating, Horovitz became the first Teaching Fellow of VES 50: Fundamentals of Filmmaking. But due to the Massachusetts Film Tax Credit luring major studios to shoot in Boston, he also has had the opportunity to work on commercial film. “It’s great,” said Horowitz. “I’ve TA-ed here, and on Fridays I’ll PA [work as a Production Assistant] on a hundred-million-dollar movie.”

Massachusetts-made SHUTTER ISLAND is the number one movie in America.

The growth of the film industry here ought to prompt a wider discussion about general tax policy. It is the film industry that is in focus right now. But it is actually about every industry. It is the private sector that creates the jobs that produce the tax revenue that is the lifeblood of government. If government keeps raising the price of doing business here, it will ultimately collect less and less.

It’s nice to spot Leonardo DiCaprio in Nahant or Bruce Willis in Lynn, but Massachusetts House Speaker Robert DeLeo said business is the biggest reason to bring Hollywood to the Bay State. His view is underscored by a recent University of Massachusetts study concluding the state’s efforts to lure Hollywood stars has transformed Massachusetts into one of the nation’s fastest-growing locations for film and television production with a 117 percent growth in motion picture and video production jobs in the state between 2005 and 2008.

Oddly, Professor Enrich makes no reference to UMass’ recently published, independent, 18 month study on the local economic impact of the MA film industry since 2006. According to that study, nearly 7,000 jobs were created in 2008 alone. Even if you attribute only 75% of those jobs to the credit, the cost-per-job is just $18,000. The professor was correct about one thing, film jobs pay an average annual salary of $68,000. Hardly a “losing bargain.”

Just in the past couple of years, the local area has hosted several movie projects. Scenes from “Bride Wars,” starring Anne Hathaway and Kate Hudson, were filmed in Salem. Parts of “The Proposal,” starring Sandra Bullock, Ryan Reynolds and Betty White, were filmed in Beverly and Manchester. “The Company Men,” starring Ben Affleck, Kevin Costner and Tommy Lee Jones, features scenes shot in Marblehead. Capping the film tax credit isn’t so much about making those in the film industry angry. It’s about a short-term gain that will very likely create a long-term loss.

This incentive is not just about actors, directors, producers or studio owners who benefit from the program. It’s about local businesses and workers, some in sectors that have been particularly hard hit by the recession, such as construction and transportation. Jobs and private-sector economic activity are what produce the long-term, sustainable tax revenue that the state desperately needs. So while Essex reaped $150,000 as a town from “Grown Ups” using Centennial Grove, it’s more notable that the summer-long film work injected an estimated $1 million or more into the Essex private-sector economy. It would be foolish, not to mention expensive, to drive that activity to other states.