The rise of humans from fearful creatures huddled around cave fires to the dominant species on the planet largely parallels the evolution of weaponry. Different subgroups rose and fell, spreading their culture or declining in influence as they either came up with the new best thing with which to slaughter their neighbors or fell behind in the innovation game.

Club, axe, spear, atlatl, sword, longbow, crossbow, catapult, gun, bomb, artillery, really big bomb -- all have had their day.

We even delineate historical epochs by naming them after the dominant weapon technology of the time: Stone, Bronze, Iron, and the modern era, which might accurately be termed the Gunpowder Age.

Over time, the one constant has been to invent a technology that conferred an advantage on the user in battle -- or else served as protection against what the other guy had. And the reason for wielding any given weapon has always been to maim or, preferably, kill one's adversary. Before one got one's own self killed, of course.

And Then, Someone Had a Whole New Idea

The concept of a weapon that is designed merely to temporarily incapacitate, with little or no lasting injury, is relatively new.

In a way, the development of nonlethal weaponry (NLW) can be seen as an inevitable byproduct of the rise of democracy in the world. In nations ruled by autocracies of one kind or another, the citizenry must be kept in line with ruthless efficiency. Not even the smallest challenges to the established authority structure can be ignored. Critics are hunted down, jailed, tortured, murdered, dumped into mass graves.

Where power is (at least theoretically) vested in the people, on the other hand, dissent is generally tolerated, even encouraged. Killing one's countrymen, even if they are political opponents, is considered really bad form. There are laws against it. And elected officials hesitate to raise too heavy a hand, lest they alienate constituents, get voted out, and be stripped of their power and all those nice perks of office.

But this doesn't mean that there is no demand for crowd control. It remains just as much a necessity. Groups of citizens may be allowed to gather and raise their collective voice in protest, but they are not allowed to stage assaults on the people's representatives.

At the same time, policing has undergone significant change. Hanging alleged wrongdoers on the spot is no longer sanctioned. "Wanted Dead or Alive" posters have disappeared. Cops carry guns that are supposed to be used for defensive purposes only. In general, law enforcement officers are expected to arrest suspects and convey them to a holding cell while causing minimum physical damage.

Mobs, however, can become unruly and refuse orders to disperse. A hardened criminal confronted by police may not be inclined to go quietly. The state and its appointed protectors need ways of dealing with such problems: ways that try to avoid death or serious injury to citizens who, malefactors though they may be, still retain certain basic rights.

There are warfare applications as well. As Wikipedia puts it, nonlethal weaponry may be used "in combat situations to limit the escalation of conflict where employment of lethal force is prohibited or undesirable, where rules of engagement require minimum casualties, or where policy restricts the use of conventional force." One might also add "the need to conserve resources" and "the desire to spare the environment" to that list.

With a wide-ranging potential market up for grabs, technology specialists were bound to invent devices to fill every conceivable niche. Thus the advent of nonlethal weapons was a given.

First on the Scene: Gas

Originally developed as killing agents in World War I, deadly gases evolved into nonlethal versions, such as tear gas, a generic term applied to about 15 different aerosols, but primarily either CN or CS, with the latter being the most popular nowadays. The effects of tear gas range from mild tearing of the eyes to more serious reactions.

CN is somewhat more toxic than CS, but it was the first to market. The US Army's Chemical Warfare Service promoted it for civilian use after World War I, and by the mid-1920s it was a common weapon in police arsenals. CN endures to the present in personal canisters as Mace, a trade name turned generic, although it has largely been replaced in pockets and purses by the more-popular pepper sprays containing capsaicin, ultimately derived from chilis.

While CS, CN, and pepper spray are all considered NLWs, there is no question that they can cause serious injury and, under certain circumstances, death. CN can damage the cornea and has been implicated in deaths from pulmonary damage and/or asphyxia. CS can also cause pulmonary problems and, according to the Journal of the American Medical Association, can significantly damage the heart and liver. Pepper spray, widely considered the most "humane" alternative can, according to a report from the North Carolina Department of Health, cause responses including "burning of the throat, wheezing, dry cough, shortness of breath, gagging, gasping, inability to breathe or speak (due to laryngospasm or laryngeal paralysis), and, rarely, cyanosis, apnea, and respiratory arrest."

Enter the EMIs

Next on the scene came the electromuscular incapacitation devices, or EMIs, of which the most well-known is the TASER®.

The modern Taser arrived with a patent filed by inventor John Cover in 1974. Although most people probably think the term is a scientific acronym, along the lines of "laser," it isn't. Cover playfully named his new device after one of his fictional childhood heroes: the Thomas A Swift Electrical Rifle, and in his patent application described it thusly:

"A weapon for subduing and restraining includes a harmless projectile that is connected by means of a relatively fine, conductive wire to a launcher which contains an electrical power supply. The projectile is intended to contact a living target without serious trauma and to deliver an electric charge thereto sufficient to immobilize."

We can accept that Cover was well intentioned, but as with other NLWs, the Taser's capacity for inflicting "serious trauma" (and possibly death) on the recipient can no longer be questioned.

At the same time as the first Taser was rolled out, R&D was under way on a wide variety of pocket stun guns, stun flashlights, and stun batons that were put to police use by the late 1980s and eventually came to be marketed to the public for personal self-defense in close-quarters situations.

Today, a small unit like the one below can easily be purchased online. This particular model features a handy pin at the base that pulls out and renders the gun useless should your opponent wrestle it away from you.

Handheld devices operate on the same principle as the Taser, i.e., they deliver a high-voltage, low-amperage shock to the system that causes disruption of muscular control. Stun guns are offered with up to 5 million volts of power and, though that may sound like enough to wipe out an entire gang of bad guys, it's the amperage that really matters. Just 0.06 of an amp (i.e., 60 milliamps) is sufficient to cause death in many cases, so these devices are typically calibrated to single-digit milliamperages, which should incapacitate without killing.

A stun gun's effectiveness in an actual life-and-death situation is at least questionable. Unlike the Taser, it doesn't operate at a safe distance from the threat. In addition, the longer the arc between the electrical contact points, the greater the effect. That gives Tasers another advantage, in that their projectiles spread out before hitting the target and will typically drop the assailant to the ground since the current is moving over a larger muscle area. Because of stun guns' smaller arcs, they can require several seconds of contact before the effects kick in, and that might be too long. Manufacturers, however, tout their products by saying that the pain of the initial contact, or merely flashing that electric arc, will cause an attacker to back away from you (um, well, maybe it will -- but that isn't likely if he has a firearm).

Since the Taser acronym contains the word "rifle," it was only a matter of time before a weapon would be developed that truly fit the name. That time has come. Taser International has introduced its XREP model, which allows for delivery of the shock device at long distance.

Despite the easy availability of EMIs, their legal status must always be considered. They are banned for private use in many countries, and either banned or restricted in nine US states and a half-dozen cities and counties. Be aware of your local regs.

And no NLW has come under as much criticism as EMIs, mainly because they are not always nonlethal. In one case that received national attention, a Vermont state trooper used a Taser to kill an unarmed, 39-year-old epileptic man in June of 2012.

With death always a possibility, one would think that Tasers would not be employed lightly. But because they are regarded as usually harmless, that has hardly proven to be the case.

Coherent Light: Tech Moves Beyond Gas and Shock

As electrical incapacitation devices were being produced, there was no lack of research in other areas. The Early History of "Non-Lethal" Weapons, a 2006 paper from the University of Bradford, UK, notes that by the late 1970s, most varieties of the NLWs we know today had already been conceived. Many were in use, being tested, or under development, including:

• Kinetic NLWs: Water cannons and projectiles (in use); nets (available, not in use)
• Electrical: Stun guns and TASERS (in use); wireless electric weapons (proposed)
• Chemical: Tear gases and smokes (in use); lubricants and aqueous foams (available, not in use); sticky foams and malodorants (in R&D)
• Biological: Incapacitating bacteria, viruses, and toxins (available but banned by the 1972 Biological and Toxin Weapons Convention)
• Optical: Flash-bang grenades and high-intensity lights (in limited use); stroboscopic lights (in R&D)
• Acoustic: Audible sound generators (in limited use); ultrasound/infrasound generators (in R&D)
• Directed energy: Laser and microwave devices (in R&D); vortex generators (proposed).

Although there have been a number of innovations since then, most of what's been accomplished has to do with refining the product.

Laser weapons, for example, are well out of the R&D stage, despite the fact that their use was banned on the battlefield by the 1995 Vienna Conventional Weapons Convention. The US was a signatory to that protocol.

Nevertheless, we now have various "dazzlers" that operate in either the red or -- primarily because it works better in daylight -- the green areas of the spectrum. Their purpose, according to the Department of Defense's Non-Lethal Weapons Reference Book: "Force protection, entry control points, checkpoints, and maritime ports and security zones to warn, deny, move, and suppress (e.g., distract, disorient, and degrade) individuals on foot and those operating vehicles/vessels."

Dazzlers are designed to emit coherent light beams that are less tight than with conventional lasers, in order not to cause permanent eye damage. There are a large number of models; one is the PHaSR or Personnel Halting and Stimulation Response rifle, which was developed in-house by the US Department of Defense.

Another, the Glare Mout, is a green laser that spreads to a larger spot at the intended target, making aiming the device at long distances or at multiple subjects much easier. The Glare Mout's effective range is 150 meters to 2 kilometers. Of course, you don't want to use it at close range, i.e., within the NOHD (that's bureaucratese for the "nominal ocular hazard distance"). That would cause permanent blindness, and the Glare Mout's range finder thus has a precautionary, automatic shutoff at 65 meters.

The StunRay is an optical incapacitation effector developed by Genesis Illumination that uses collimated (slightly less than laser) broad-spectrum visible and near-infrared light from a short-arc lamp to safely and temporarily impair vision, disorient, and incapacitate aggressors for 5 seconds to 3 minutes without causing physical harm.

The Saber 203 dazzler uses a 250 mW red laser diode, mounted in a hard plastic capsule in the shape of a standard 40 mm grenade, suitable for being loaded into an M203 grenade launcher. It has an effective range of 300 meters.

But that's nothing compared with the long-range ocular interruption (LROI) weapon presently under development by the Navy. That one is projected to be effective up to 3,000 meters, or nearly two miles.

And so on. There are lots of these things. While dazzlers per se are prohibited for personal use, green lasers are sold as adjuncts to pistols and rifles. For aiming purposes only, but...

Optical NLWs are not limited to laser devices, either. There is, for example, also a weapon called the Dazzler, a very bright, stroboscopic LED flashlight that causes nausea, dizziness, headache, flash blindness, eye pain, and sometimes vomiting. The Dazzler was developed for the Department of Homeland Security, but is expected to be made available to local law enforcement in the near future. In the meantime, plans for a DIY version can be found on the Internet.

Can You HEAR Me Now?

Acoustic weapons have also taken giant strides forward since the '70s, with the most well known probably being the long-range acoustic device (LRAD), or "sound cannon." The LRAD broadcasts focused, very loud sound over longer distances than is possible with normal loudspeaker systems. It can be used to send messages and warnings, but also to cause extreme pain.

For comparison purposes, normal conversation takes place at about 60 decibels (dB). Depending on the person, the pain threshold for an individual is about 130 dB. The LRAD's maximum continuous level is 162 dB.

LRADs were originally developed for the military to create safe zones around naval vessels, but they have become features of many police departments and some private enterprises, as well. Among the latter is the cruise ship Seabourn Spirit, which was carrying one when attacked by pirates off the coast of Somalia in November of 2005. The pirates had machine guns and RPGs, but the ship was able to repel the assault by turning the LRAD on them.

An LRAD was used for the first time domestically to disperse those protesting at the G20 Summit in Pittsburgh in September of 2009.

One of the problems with the LRAD is that its effects can be permanent. A woman who was watching the Pittsburgh demonstration suffered "permanent hearing loss, nausea, pain, and disorientation" from her exposure to the machine, according to a lawsuit she filed against the city and its police department. In addition, there's some evidence the LRAD can cause fatal aneurysms. On the practical side, critics also question the value of an expensive NLW whose effectiveness can be defeated with earplugs.

A new entry into the acoustic NLW arena is the Inferno Sound Barrier. It doesn't make people run from it because of loudness -- although at 120 dB, it's pretty darn loud. It repels because the sound it emits combines four frequencies spread out over 2-5 kHz. Those frequencies mixed together have a deeply disturbing effect on people, causing them to flee within seconds.

The Inferno, a Swedish import, was originally designed to protect public buildings, retailers, and boats, but the manufacturer intends to market it to commercial vehicles like taxis, and to law enforcement for riot control. It's almost sure to eventually find its way into private residences, as well.

Then, in the "best of both worlds" category, we have the flashbang or stun grenade, which combines optical and auditory incapacitating qualities in a nice, compact package. The device was first developed by the British Army's elite SAS division in the 1960s. Basically, it's a grenade without the fragmentation, designed to remain intact after detonation, while releasing all the light and sound of the explosion through holes in its casing.

The flash part momentarily activates all photoreceptor cells in the eye, making vision impossible for about five seconds, until the eye resets itself. The bang part causes temporary loss of hearing and also disturbs the fluid in the ear, leading to loss of balance.

Flashbang grenades have migrated to police use and have been effective in hostage situations. Unfortunately, the heat produced by the blast can ignite combustible materials in the vicinity and lead to deaths, as was the case with an elderly couple in Minneapolis in 1989, when they were mistakenly targeted as drug dealers and died in a SWAT assault that caused a grenade-started fire. The shock from a flashbang has also induced at least one fatal heart attack.

Flashbangs are normally thrown by hand, but there are other delivery systems. VENOM (Vehicle Non-Lethal/Tube Launched Munition System) is a 40mm, multi-shot, electrically actuated grenade launcher mounted to the Marine Corps Transparent Armored Gun Shield turret. The system consists of three banks of ten launch tubes, each at fixed angles of 10, 20, and 30 degrees from horizontal, achieving 360-degree coverage, with a range of 400 feet. Flashbangs can also be rigged to be delivered as an airburst weapon with an increased applicability zone.

Also combining optical and acoustic deterrence is the large, vehicle- or ground-mounted distributed sound and light array (DLSA) system, currently being prototyped by the military.

Other Exotica

Another class of NLWs is shock wave generators, intended simply to knock folks down. The big daddy of these devices -- which essentially direct the shock waves from controlled explosions -- is the Thunder Generator, originally devised by Israeli farmers to scare away birds. But the Israeli government has an interest in using it for crowd dispersal, since it can upend people at a distance of up to 100 meters. Problem is, if someone strays to within 10 meters, he's apt to wind up dead.

A related weapon is the Vortex Ring Gun, which creates high-energy gas vortices that can be directed at a target to knock it over. The rings can also be made to carry chemical payloads -- such as tear gas, pepper spray, or nausea-inducing malodorants -- that then adhere to the person struck by them.

Speaking of malodorants, there are many of them, such as Skunk, used for crowd control by Israeli Defense Forces since 2008. Skunk is dispersed as a mist fired from a water cannon. It leaves a terrible sewage odor on whatever it touches and does not wash off easily. A sudden change of wind direction could be a problem here.

The Mobility Denial System, also known as "instant banana peel," is a weapon invented a few years back at the Southwest Research Institute. It disperses a thick, slippery gel onto asphalt, concrete, wood, and even grass, making movement impossible without falling down. Vehicles slip and slide as well. The downside of course is that you can't operate in the treated area any more than the opposition can.

The Pulsed Energy Projectile is currently under development by the military. It involves a weapon emitting an invisible laser pulse that, upon contact with the target, ablates the surface material and creates a bit of exploding plasma on the skin. This produces a pressure wave that stuns the target, knocking him down, as well as electromagnetic radiation that irritates nerve cells, causing pain.

The military's Active Denial System (ADS), also known as the pain ray, has gotten a lot of media attention. This truck-mounted machine, perfected in 2007, beams electromagnetic radiation -- similar to that produced by a microwave oven -- at the target and causes an intense burning sensation. Proponents swear that the ray only causes the "impression" of burning, because it barely penetrates the skin -- just enough to make your nerve endings think you're on fire. Demonstrations have been conducted on volunteers, and the principle has been validated, although field tests remain to be carried out.

The ADS was deployed in Afghanistan, but it was recalled without having been used. Potential problems that have been suggested include: ineffectiveness in bad weather; lack of penetration of thick clothing; and inability to selectively target individuals in a crowd. But research continues. The Air Force would like to have an airborne ADS (think drones), but the obstacles are formidable, and that one is just in the conceptual stage. Smaller, man-portable units may be closer to reality.

Sticky Foam guns fire a goo that consists of nontoxic but extremely tacky and/or tenacious materials that solidify when they hit the target, entangling an individual and impairing movement. The downside is the possibility of suffocation if the person is hit in the face. Sticky foam was reportedly used by the Marines as part of an operation in Somalia.

The Netgun looks like an oversized flashlight; it fires a net which entangles the target. A larger version, suitable for use in crowd control, is under development.

Upon detonation, the Stingball Grenade propels a cache of 100 tiny rubber balls in a circular pattern. The Modular Crowd Control Munition (MCCM) is the Stingball's tightly directed big brother. It's constructed like a Claymore mine but with 600 rubber balls inside that are sprayed out in a 45-degree arc.

Nor have swimmers been forgotten. Future scuba divers bent on attaching mines to ships will meet resistance in the form of an underwater pulsed sound wave that is sure to drive them off if they get within 150 meters. It's under development by the Navy.

Just over the horizon: Sierra Nevada Corp., working under a US Navy contract, is reportedly ready to build a microwave ray gun called the MEDUSA (Mob Excess Deterrent Using Silent Audio). The device fires short microwave pulses that penetrate the head and rapidly heat tissue, resulting in a shockwave inside the skull.

Finally, we shouldn't leave this subject without a quick mention of one of the more whimsical of recent NLW inventions, the speech jammer gun developed by some Japanese tinkerers. This device is not intended to incapacitate anyone, just to shut them up. Effective at up to a hundred feet, you simply aim it at someone who won't stop talking, and it broadcasts the speaker's own words back at him with a 0.2-second delay, causing him to become completely tongue-tied and unable to go on. Poetic justice indeed. Hmmm... We can think of a whole lot of Washingtonians (DC denizens, not the Pacific Northwest state citizens) we'd love to try this thing out on.

NLWs: An Ongoing Experiment

As noted at the outset, NLWs are a recent arrival on the human scene, and we're still experimenting with the proper ways in which to use them. As a means of responding to threats from our fellow humans without having to kill them, these weapons are surely an improvement over brute force. However, there are some issues involved, and the need to deal with them is extremely important.

At the end of the day, it's important to remember that technology is completely neutral. It will evolve with no regard to how it is used. It is exactly this sort of evolution that is tracked very carefully in Casey Extraordinary Technology. Readers are plugged into the world's most revolutionary breakthroughs - and not just in weaponry. Advancements in the fields of biotechnology have recently netted subscribers exceptional gains.

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