

Adam Lanza, the killer of 26 people at an elementary school in Newtown, Connecticut, was raised by a woman, Nancy Lanza, who, her sister-in-law told reporters, was obsessed with guns and "prepared for the worst". With fears of an imminent economic collapse on her mind, Nancy Lanza is said to have stockpiled weapons and had an affinity with the "prepper" movement, an informally organized network of Americans convinced that looming disasters, ranging from the death of a family member to a Biblical apocalypse, require total self-sufficiency.

Lanza's paranoia and mistrust of authority may have contributed to her pulling her troubled son out of school, home-schooling him in a cloistered environment. On Friday, he murdered her with one of the assault rifles she owned.

In April 2009, at the dawn of the Obama era, I toured a series of gun shows in the American west. There, I encountered a subculture that closely reflected the survivalist mentality embodied by Nancy Lanza. Heavily armed and tightly organized through one of the most powerful political lobbies in the country, many of the gun show attendees I met had been incited into a paranoid frenzy by rightwing talk radio.

"People are worried about what's going on in government," a gun dealer with a silver mullet and a .45 caliber pistol strapped to his belt told me outside a gun show at a Reno, Nevada casino. "So consequently, people are preparing for the worst."

"When they start imprisoning Americans, and people start seeing that we're the enemy, then that'll make it hot," a 20-something man sporting a button for former Republican presidential candidate Representative Ron Paul told me in the parking lot outside a gun show in Antioch, California, a Republican stronghold about an hour east of the San Francisco Bay Area. "People talk about a revolution," the young man continued, "an armed revolution. I think police crackdowns on individuals will tip the scales."

An older gentleman in a floppy camouflaged baseball cap manning a National Rifle Association (NRA) booth outside the Antioch gun show rattled off conspiracy theories popularized by the far-right radio jock Alex Jones. He warned me that the government was planning to round up "normal citizens" and throw them in concentration camps operated by the Federal Emergency Management Agency (Fema):

"In fact, Obama's own campaign promise was to develop a 20,000 man civil army to patrol the streets of America that he will build up stronger than our own military, and so this is all part of the program that's coming down the pike."

The NRA representative said the flagging economy and ensuing political panic had translated into record gun sales. "We've been swamped today," he claimed. "We've practically ran out of our materials that we give away at sign-up." Before I was able to enter the gun show, the man compelled me to pay a $30 fee to join the NRA.

In the months that followed, I was bombarded with NRA fundraising pitches, paraphernalia, and newsletters warning of the latest liberal plan to strip average Americans of their gun rights. One NRA mailer beseeched me to start a chapter in my neighborhood in Brooklyn, New York, promising me the honor of local chapter president.

Many of those I interviewed at the gun shows were common hunters, sportsmen, and expert target shooters. One man told me he hunted deer with a bow and throwing knives, a family tradition he learned from his grandfather. For them, guns were a part of daily life, enabling their interaction with the rugged western environment in which they were raised.

But then there were others seeking out military-grade sniper rifles designed specifically to kill humans with deadly accuracy from hundreds of meters away. Though the exemption covers all "private sales", not limited to gun shows, the so-called "gun show loophole" means that two in every five guns are acquired without a federally-mandated criminal background check.

Inside the Reno casino, I sidled up to a group of gray-haired men gathered around an exhibition table where a dealer from Nemesis Arms was touting the features of the Mini Windrunner .308 caliber sniper rifle. (Adam Lanza's weapon of choice was a .223 caliber Bushmaster assault rifle.) According to Defense Review, a leading online newsletter covering the small arms industry, the gun was a "nasty little piece of manpackable/backpackable ballistic business!" With the sleek, 3ft-long rifle in his hand, the dealer explained:

"The bipod will articulate to the side. You can shoot off of walls, car or truck doors, building tops, cliffs – at any angle, all the way to barricade position."

In less than a minute, the dealer effortlessly disassembled the gun and packed it away discreetly in a black backpack, explaining:

"The reason that we don't do this in a molly pack is that it looks military. If it's military, then people will assume that you're military. So what we do with this is we keep it as benign as possible so it looks like just any other backpack that anybody would have … so anybody with any garb, any dress, can go anywhere with it."

Why would a common civilian need a sniper rifle capable of shooting off of building tops and car doors? And why would they require stealthy methods of concealment, so they could pass through American cities without detection? Companies like Nemesis Arms never explained the logic behind such disturbing sales pitches. But clearly, they were falling on fertile soil.

With Democratic lawmakers and liberal activists pressuring President Barack Obama for new gun control legislation in response to the Newtown massacre, rightwing survivalist types and the gun lobby are prepping for the disaster they fear the most. As a young man stroking a .45 pistol outside the Reno gun show told me: