Its mission seems as humane as it is clear: to develop "weapons that are explicitly designed and primarily employed so as to incapacitate personnel or material, while minimizing fatalities, permanent injury to personnel, and undesired damage to property and the environment."

To some critics, however, the Joint Non-Lethal Weapons Directorate (JNLWD), established by Congress in 1997 under Marine Corps command, is obsessed with developing a high-tech arsenal that contravenes U.S. and international law.

"Forcing drugs on large crowds of civilians is not a cool and high-tech war of tomorrow," said Edward Hammond of the Sunshine Project, an international network of activists against biotech weapons. "It's not gee-whiz, it's not Star Trek, it's not our big, bright technological future. It is sick and repugnant.... It is illegal."

Other critics contend non-lethal weapons are too soft a solution. According to a report by Lt. Colonel Margaret-Anne Coppernoll of the Army National Guard, non-lethal weapons "not only fail to strengthen the nation's position when dealing with (irrational) adversaries but convey that it is too squeamish to inflict serious harm on enemies or to accept casualties."

But one member of a National Academy of Sciences panel assessing the role of non-lethal weapons maintains that the truth is situational.

The panel member, who requested anonymity pending the release of the group's report later this year, said: "There is no such thing as a lethal or non-lethal weapon; the determinant is the application."

The panel member used the Cold War nuclear arms race to illustrate the point.

"It is a tough stretch to envision a scenario for the non-lethal application of a nuclear bomb, yet we and the Soviets fought the Cold War almost entirely with nuclear weapons. And, at least after the long-term effects of exposure to radiation were understood and taken into account in testing, we never killed a soul," the panel member said.

"All those latter-day nuclear bomb tests weren't really tests – the science was proven. They were the strategic use of the most deadly weapons ever invented to impress and give pause to a sworn enemy who might be considering an attack.

"The amazing thing was it worked brilliantly. Nuclear deterrence was the most successful enforcer of peace between superpowers in the history of mankind."

The source cited "taggants" – invisible bio-organisms that are painted on a small part of a structure, grow until they cover the entire building, and can be remotely triggered to illuminate and provide a homing signal for bombers or missiles – as an example of an "ethically neutral" JNLWD project.

"Paint a taggant on an oil-storage tank and it's a non-lethal weapon," the panel member said. "Paint it on a munitions factory and it's a lethal weapon."

A survey of a few JNLWD projects makes clear the difficulty of classifying non-lethal weapons technologies.

Item: calmatives, better known as psychotropic, central nervous system depressants or, more simply, downers. The JNLWD is studying their use – including such substances as fentanyls (an ultra-potent, heroin-like synthetic) and rohypnol, aka "roofies," the so-called date-rape drug – as crowd-control mechanisms. Opponents say the use of all such drugs is banned by the 1993 Chemical Weapons Convention.

The Sunshine Project claims the JNLWD has an "advanced development program for long-range delivery devices for (such) chemicals, in particular a 'non-lethal' 81mm mortar round with a range of 2.5 kilometers which is designed to work in standard-issue U.S. military weapons (like) M252 mortar."

The anti-bioweapons group also accuses the JNLWD of considering the use of the sedative Precedex, which increases a patient's sensitivity to electroshock, as an instrument of torture.

Item: active-denial weapons (ADWs), which fire wide-angle 95 gigahertz electromagnetic waves that heat water molecules in the outer skin and cause debilitating pain. Critics contend ADWs target innocent bystanders as well as enemies, and say the temptation to crank up the power to "kill" level may prove irresistible.

Item: genetically engineered anti-material agents (GAMAs), man-made micro-organisms that eat things like concrete, metal, asphalt, paint and plastic. GAMAs could theoretically be used to slowly and stealthily destroy military airstrips – or create World Trade Center-magnitude disasters.

Opponents say GAMAs violate a Geneva Protocol, ratified by Congress in 1975, prohibiting bacteriological weapons. Proponents say non-lethal bioengineered substances are exempt.

Item: veiling-glare lasers. Researchers hope wide-angle laser beams in the violet to ultraviolet spectrum will blind enemies by making their eyes fluoresce, that is, glow.

The JNLWD says temporarily blinding enemies is legal under a 1996 Geneva Convention vision-weapon protocol. Critics say such weapons could cause permanent eye damage, making them illegal.

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