AFTER THE NEWTOWN, Conn., massacre, the National Rifle Association promised to “offer meaningful contributions to make sure this never happens again.” Friday, the gun owners and manufacturers lobby called for stationing an armed guard in every school in the country. “The only thing that stops a bad guy with a gun is a good guy with a gun,” said the organization’s executive vice president, Wayne LaPierre. “Would you rather have your 911 call bring a good guy with a gun from a mile away or from a minute away?”

This is not a fresh idea; the NRA responded to the mass shootings at Virginia Tech in 2007 and at Columbine High School in Colorado in 1999 with similar comments. It is not unreasonable where local schools feel they need armed guards. But the notion of thousands upon thousands of additional gun-carrying guards roaming school halls strikes us as impractical and unwelcome. Where would these new guards come from, would they really be trained and what additional margin of safety would be achieved? Do local police think this is a good idea? Mr. LaPierre’s simplistic slogan about stopping a bad guy with a gun ignores the reality that mass shootings are usually scenes of mayhem and crossfire, not a movie lot where a hero stops bad guys in their tracks. Would an armed guard have stopped Adam Lanza, or would the guard have been mowed down by Mr. Lanza’s semiautomatic rifle, as were the school principal and other courageous teachers and school officials?

Mr. LaPierre raised some questions that should be addressed. Gun violence in films and video games is often glorified, gratuitous and distressing. News coverage of terrorism and two major wars in the past decade has been saturated with images of weapons and death, perhaps unavoidably. This is woven into our time and culture, a complex tapestry of experience and values that demands examination and introspection.

Unfortunately, Mr. LaPierre’s approach was crude, railing against the “moral failings” of the media as “silent enablers, if not complicit co-conspirators” in bringing children cheek by jowl to gun violence. “In a race to the bottom,” he said, “many conglomerates compete with one another to shock, violate and offend every standard of civilized society, by bringing an even more toxic mix of reckless behavior and criminal cruelty right into our homes.” This sounds like a smokescreen, intended to obscure something else.

Indeed, Mr. LaPierre dodged the really big question: When will we muster the common sense to prohibit the sale of military-style assault weapons to civilians? President Obama has promised rapid action to revive the ban on semiautomatic rifles that expired in 2004 and still makes sense. These guns, such as the Bushmaster that Mr. Lanza used to kill 26 people at Sandy Hook Elementary School, are modeled on military weapons. They load and shoot rapidly. Mr. La­Pierre asked, “Since when did ‘gun’ automatically become a bad word?” We would respond: Why do we allow weapons designed for war to be bought and sold on our streets?