Editor's note: David Frum, a CNN contributor, is a contributing editor at Newsweek and The Daily Beast. He is the author of eight books, including a new novel "Patriots" and his post-election e-book, "Why Romney Lost." Frum was a special assistant to President George W. Bush from 2001 to 2002.
(CNN) -- The National Rifle Association's Friday press event has received almost uniformly negative reviews. Yet the speech by NRA chief Wayne LaPierre had this merit: It pulled into daylight for all to see the foundational assumption of modern American gun culture.
LaPierre argued that our society is stalked by unknown numbers of monsters, potential mass murders like Adam Lanza. Then he said this: Even if we could somehow identify future Adam Lanzas, "that wouldn't even begin to address the much larger and more lethal criminal class: Killers, robbers, rapists and drug gang members who have spread like cancer in every community in this country."
The "criminal class" sentence is key. In LaPierre's mind, the world is divided between law-abiding citizens and dangerous criminals. Citizens and criminals form two separate and discrete categories. The criminals pose a threat; if the citizens do not go armed against the threat, they will be victimized by the threat.
I know people who carry handguns with them wherever they go, and for just the reason described by LaPierre.
Now let's take a look at the real world of American gun ownership. The following incident occurred in August:
"A man was shot in the face 9 p.m. Friday in an altercation with a neighbor over barking dogs on Atlas Street," Troy Police said.
"Police arrested David George Keats, 73, of Troy [Michigan] and charged him with attempted murder in the incident," according to a media release from the Troy Police Department.
"According to police, witnesses stated that the altercation began when Keats let his three dogs outside and the dogs began to bark. According to the media release, Keats' 52-year-old next door neighbor yelled at the dogs to be quiet and kicked the fence. Keats then ran up to the victim, yelled, 'Don't tell my dogs to shut up,' and began shooting at the victim.
"One bullet hit the man in the face, piercing both cheeks, and four more shots were fired at the victim as he was running away," according to the report.
The encounter between Keats and his neighbor ended nonlethally only by good luck. A shot in the face is a shot to kill.
Nor was this encounter aberrational. There's solid research to show that most so-called defensive gun uses are not really defensive at all.
In the late 1990s, teams of researchers at the Harvard school of public health interviewed dozens of people who had wielded a gun for self-defense. (In many cases, the guns were not fired, but were simply brandished.) The researchers pressed for the fullest description of exactly what happened. They then presented the descriptions to five criminal court judges from three states.
"The judges were told to assume that the respondent had a permit to own and carry the gun and had described the event honestly from his/her own perspective. The judges were then asked to give their best guess whether, based on the respondent's description of the incident, the respondent's use of the gun was very likely legal, likely legal, as likely as not legal, unlikely legal, or very unlikely legal."
Even on those two highly favorable (and not very realistic) assumptions, the judges rated the majority of the self-defensive gun uses as falling into one of the two illegal categories.
The researchers concluded:
"Guns are used to threaten and intimidate far more often than they are used in self-defense. Most self-reported self-defense gun uses may well be illegal and against the interests of society."
That certainly describes the Keats shooting. With a little Google searching, you can pull up dozens of similar incidents.
Here's a story from just this past week, December 22.
"Longview, Washington -- A man shot and killed his uncle during an argument at their apartment complex late Friday night. ...'We heard a big bang,' said Ron Nelson, who lives a few apartments down...Nelson said the men were fighting over a hat and a cell phone."
Now that so many Americans carry weapons when they go out of the home, shooting incidents can occur anywhere, including very commonly the road. Another recent incident: In Pensacola, Florida, in October a man in a Jeep Cherokee cut off another car. A roadway confrontation followed, the two cars stopped, and the Jeep owner emerged to shoot the other driver in the knee. He was arrested this past week.
In these cases, and thousands like them each and every year, it is not so clear who is the "good guy" exercising responsible self-protection and who is the "bad guy" who can only be deterred by an armed citizen.
But the guns in their hands protected exactly nobody. They turned ordinary altercations into murderous exchanges of fire. They brought wounds, death and criminal prosecution where otherwise there would likely only have been angry words or at worst, black eyes.
LaPierre's offers a vision of American society as one unending replay of the worst scenes in Charles Bronson's 1974 vigilante classic, "Death Wish."
The people most victimized by this nightmare vision end up being the people who believe it -- and who carry the weapons that kill or maim their neighbors, their relatives, their spouses, and random passersby.
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The opinions expressed in this commentary are solely those of David Frum.