It has become one of the most popular…and one of the most infamous…weapons in American history.

The Colt AR-15, often known as an assault rifle, has captured the imagination of gun enthusiasts who are drawn to its sleek form, portability, ease of use, easy maintenance and upkeep, and relative low cost of ammunition; as well as a mystique in connection to the M-16, its Vietnam War combat cousin.

Part of the appeal of this firearm stems from the ability to “accessorize it” to your own personal preferences, including extras like interchangeable optics systems and gun barrels, and different stock and forearm arrangements.  Its military pedigree and appeal to hobbyists has helped spur sales of 5 million AR-15s in the last 20 years, with most of those sales coming in just the past six years.  According to industry figures, nearly one of five guns sold in the U.S. is now a semi-automatic AR-15-style rifle.

Adam Lanza used a similar model of the gun to kill 26 people — 20 of them children – at an elementary school in Newtown, Conn. last Dec. 14.

Months earlier, James Holmes allegedly opened fire with the weapon in a movie theater in Aurora, Colo., killing 12 people.

And suspected L.A. airport gunman Paul Ciancia, accused of killing a TSA agent and wounding three others, allegedly fired dozens of rounds inside LAX with yet another variation of the gun, a Smith & Wesson 223 M&P-15 assault rifle.

(Please note that these three examples involved similar types of assault weapons that are chambered for the 223 caliber round, but are all designed by different firearms manufacturers.)

These shootings have sparked calls to revive a lapsed federal ban that outlawed military-style semi-automatic weapons and their features, notably high-capacity, detachable magazines.

But even with the renewed drive to ban them, AR-15-style rifles appear to have attained a level of cultural currency rivaling the six-shooter that “Won the West” and Dirty Harry’s .44 Magnum.

The AR-15 was designed in the 1950s by ArmaLite, a division of Fairchild Engine and Airplane Corporation, to sell to the military as a replacement for the clunky rifles of World War II, the M-1 and M-14.  But despite the futuristic lightweight design, the U.S. military didn’t want it.

By 1959, Fairchild had sold the AR-15’s manufacturing rights to Colt Firearms.  Colt embarked on a marketing blitz and in 1960, won its first important convert with the man who became famous for the phrase “bomb them back into the Stone Age.

In 1961, Curtis LeMay became Air Force chief of staff.  Under LeMay’s influence, Defense Secretary Robert McNamara ordered thousands of the weapons for the Air Force and for the military’s special forces.  Other branches of the military followed, and the military version of the gun became known as the M-16.  By the late 1960s, with the Vietnam War in full swing, the gun was a fixture among infantry soldiers, despite widespread reports of jamming, and a grudging belief that the Russian assault rifle used by the enemy, the AK-47, was a better fit for jungle warfare.

On the civilian front, however, sales of AR-15-style guns were not spectacular until recently.  Even as sales of hunting rifles have fallen, industry stats indicate that sales of guns based on the AR and AK platforms — so-called assault rifles — have spiked since 2007.  More than half a million of the guns have been purchased annually, with numbers soaring to 1 million in 2009 and hitting 1 million again in 2012, according to the National Shooting Sports Foundation.

The pace shows no sign of slowing.  According to a recent NSSF survey of gun owners, the rate of ownership of “modern sporting rifles” instead of the term “assault rifle, has increased dramatically since 2010.”  Half of all “MSR” owners had bought their first MSRs earlier this year.  In 2011, 19 percent of all guns purchased were MSRs.

Josh Sugarmann, an anti-gun-violence group, said that pro-gun forces have turned their marketing and lobbying might to military-style weapons to counter a long-term drop in overall gun sales.  They’ve found a new pitch to gun enthusiasts, he says, that combines military code words like “honor” and “duty” with a heavy dose of fear.  “The gun industry working with the NRA has become expert at using outside events to promote fear-driven gun buying,” said Sugarmann, “whether it’s the threat of federal gun legislation, the election of Barack Obama, Y2K, 9-11 terrorist attacks or the Mayan apocalypse.”

Chuck Michel, a California attorney who has defended gun owners and vendors in numerous cases, disputes the contention that the AR-15 sales pitch winks at the conspiracy-minded.  He says the weapon’s accuracy, light recoil and simplicity give it a versatility that few other weapons can match.  “It’s got a universal appeal,” Michel said, “because no matter what you want to use the gun for — hunting, target shooting or plinking — you can interchange the parts of the gun for that use.”

Despite high-profile shootings, the AR-15-style rifle is not found at many murder scenes. According to the FBI’s Uniform Crime Report, of the 8,855 homicides committed with firearms in 2012, only 322 were known to have been committed with any type of rifle. The report does not describe the type of rifles used in slayings.

But Tom Diaz, author of the “The Last Gun: How Changes in the Gun Industry Are Killing Americans and What It Will Take to Stop It,” said the stats don’t change the fact that the AR-15 and its imitators and descendants were designed for law enforcement and the battlefield.  “It’s a highly effective killing machine,” he said, “(and did) exactly what it was designed to do in places like Newtown, the Aurora movie theater and elsewhere.”  With the brisk sales of the weapon, Diaz said, “It’s not a question of if, it’s a question of when (there will be another mass killing). It doesn’t take a lot of imagination to think of even worse scenarios than Newtown.”

Although the anniversary of the school shooting at Sandy Hook Elementary in New Town, Connecticut is tomorrow and I find that to be a horrendous event that should not happen again, the weapon used is not to blame, but it is the user who takes it to the school and ultimately pulls the trigger.

You are always going to have mentally ill people who see others as threats and then take a weapon to solve their perceived problems.  So, some people say, “take away the weapon.”  Are we then going to take away all knives because someone stabbed another person, or ban all chairs because someone used one to beat another person to death?  Where does it stop?  If you want to make a difference, change the laws dealing with the mentally ill, examine the sudden upbeat in violence and the lack of empathy that exists in our young people, and if you want to ban something, then ban the sale of first person shooter video games that promote violence and civil unrest.

I have been around guns and owned guns all my life, but owning that gun never possessed me to go out and kill somebody.  Punish the criminal, not the law-abiding gun owner.