Twenty-seven killed, including 20 children. As President Obama said: “We have been through this too many times.”

By the end of this week, NAB President Gordon Smith, NCTA President Michael Powell and MPAA President Christopher Dodd have to sit down to figure out what they can do to help curb the gun violence like that in Newtown, Conn., that stunned the nation last Friday.

They have to pledge that the TV business is going to step up and become part of what should be a national, multipronged effort to stop such killing. (Dodd, a former Connecticut senator, should also rally the movie industry to the cause.)

Something is horribly wrong in America. These shootings are happening too often and are too similar to be shrugged off as random events. Much has been written about the possible causes and more will be written.

But TV doesn’t have to wait around for the definitive answers that may never come. TV can act now. What can it do?

It can stop airing so many shows that romanticize gun violence. More so on cable than broadcast these days, TV it still rife with people shooting and getting shot.

I get it. These shows are popular because they are thrilling and because they allow us to play out our own fantasies of getting justice or just getting even. Harmless? Maybe. Maybe not. Until we know for sure, the best course may be to dial it down.

TV can quit scaring people with incessant stories of violent crime. It’s no wonder millions of Americas buy guns and stick them in the nightstand drawer where they are just as likely to be used in accidental shootings, suicide or domestic violence as they are in personal defense.

(One of the great paradoxes in all this is that violent crime is going down as the spree killings go up.)

TV stations are especially guilty of the fear mongering. Because it’s easy and because viewers have a morbid fascination with it, local newscasts pack their rundowns with crime, the more sensational the better. They will even air crime stories from a half a continent away simply because they have good video from a security camera.

TV can also lead the national debate on gun violence by mobilizing its journalists. TV’s job shouldn’t end after it returns to regularly scheduled programming. National and local newsrooms should explore all the possible causes and all the possible solutions. How about a primetime documentary or two, and not on Friday or Saturday night?

The NRA should be put on the spot. Its effective advocacy has made it possible for any halfwit in the country to arm himself as if for war.

How about those point-of-view video games, which require the player to mow down the bad guys? Common sense says that that can’t be all good for the psyche.

And the TV reporters cannot shy away from questioning their own bosses. Many believe that TV is culpable, and all those critics have to do is scan the channels to show the mayhem that saturates the medium.

People want answers. Broadcasters are duty bound to seek them out.

At the very least, TV has to keep the conversation going, even if the politicians don’t. In July, in the wake of the Aurora theater shootings (12 dead), the debate over what could be done lasted all of three days.

TV is a powerful medium, reflecting and shaping our culture at the same time. Time and again, it has demonstrated that it can change the culture for the better. Here, it gets another chance.

Today, with many of the victims of Newtown still unburied, everybody is asking why, and many, including the president, are saying that it is time for action.

The TV industry can get out front on this issue, examining the impact of the programming it airs and leading the national debate.

If it does nothing on its own initiative, it may have to do it on the government’s. Over the weekend, on Fox News Sunday, Sen. Joseph Lieberman called for a national commission to examine the role of media in gun violence.

“The violence in the entertainment culture — particularly, with the extraordinary realism to video games, movies now, et cetera — does cause vulnerable young men to be more violent,” Lieberman told Chris Wallace. “Doesn’t make everybody more violent, but it’s a causative factor in some cases.”

Lieberman said that he doesn’t believe that legislation is necessarily the answer. “In our society, you always try to do it voluntarily. But, I think we’ve come to a point where you’ve got to say, if not, maybe there’s some things we can do to tone it down.”

Headed for retirement next month, Lieberman doesn’t much matter anymore. But others on the Hill — and in the White House — do.