Techniques and Gadgets

It takes only simple logic to figure out that if the battlefield conveys an advantage to the enemy, change the battlefield.

—Michael Gough, Director of Science and Risk Assessment at the Cato Institute, formerly an analyst at Congress's Office of Technology Assessment

Q. Did you ever become aware of who made the decision to initiate the use of defoliants in Southeast Asia?

A. You can't take down a smile, can you? No. I don't know who made the decision. I'm not sure after some 35 years in government if I ever identified anybody as an individual who made the decision. Decisions happen.

—Deposition of Fred I. Edwards, of the Army's Advanced Research Project Agency

In 1880, Charles Darwin noticed that plants always lean toward their source of light; he postulated that some unknown growth regulator must be at work. His observation didn't amount to much at first. It took another half-century before scientists figured out how to isolate and study botanical hormones. Researchers soon discovered that at high doses, these compounds can accomplish a lot more than nature intended. Apples and pears remain on trees until they're ripe; rooting is improved; tomatoes develop without seeds.

Even higher levels can kill. Different parts of the organism develop in awkward, bizarre ways. The plant seems out of control, as if it's growing itself to death. Scientists had stumbled upon the first selective, relatively cheap weed killers. The most successful were 2,4-D and 2,4,5-T, a close chemical relative. Both resemble the natural compound that first caught Darwin's attention, although each is about a hundred times more potent. 2,4-D kills broad-leaved weeds and is still used on dandelions. 2,4,5-T is more persistent and therefore more effective against brush and hardwoods. These compounds are manufactured as acids—hard, grainy, white crystals. When mixed with alcohol or other chemicals, they become liquids, called esters, which are easily stored and sprayed. In this book, all the acids and their various esters will be referred to simply as D and T.

During the Second World War, Dr. H. J. Kraus of the University of Chicago suggested using D and T to kill German potatoes and Japanese rice. In early 1944, the Army Chemical Corps hired him to turn both compounds into weapons. That same year, the Chemical Corps set up a full-time research center at Camp Detrick, Maryland, about thirty miles west of Washington, DC. Detrick housed both the Biological Division, which hunted for germs that could kill or disable enemy soldiers, and the Crops Division, which developed chemical and biological methods to destroy enemy food supplies.

It's no accident that both divisions were stationed at the same base. The military's definition of biological warfare has always included crop destruction. A 1950 top secret report, written by the Chemical Corps' chief of research and engineering, defined biological warfare as "the military employment of living organisms, their toxic products, or chemical plant growth regulators to produce death or casualties of man, animals, or plants." Fifteen years later, the American military would argue that D and T weren't biological weapons.

Kraus's scientific team investigated the most effective ways to use D and T. They also conducted a few toxicity studies on D, finding it essentially harmless. Kraus even claimed to have eaten one-half gram a day for three weeks. Most of this research assumed that people would only be exposed to short, high-intensity bursts of the compound. The possibility of chronic, long-term exposure was never seriously considered. Kraus's team never bothered looking into the risks of T. They just took it for granted that both compounds were equally harmless.

Toxic or not, using D and T in combat was a novel and alarming concept. Armies have destroyed enemy crops for as long as people have fought wars, but no one had ever tried doing the job with modern chemicals. To some, these compounds would transform this ancient strategy into something much more terrible. The sprays traveled too far and were much too indiscriminate; the innocent would necessarily suffer. No one was certain whether the Geneva Protocol of 1925, which banned the use of all chemical weapons, included the chemical destruction of crops (which wasn't specifically mentioned). Still, one of the diplomats who negotiated the treaty advised a colleague, "It [the protocol] prohibits every kind of chemical or bacterial weapon that anyone could possibly devise. And it has to. Perhaps someday a criminal lunatic might invent some devilish thing that would destroy animals and crops."

The Pentagon ordered its attorneys, the Judge Advocate General Corps, to determine the legality of spraying 2,4-D on German vegetables. JAG was assured that D was harmless: "This chemical is only mildly poisonous to the human body."

Some soldiers weren't concerned about legality; they despised the plan for moral reasons. In 1944, President Franklin Roosevelt received a proposal to use either 2,4,5-T or a biological weapon against Japanese rice. Admiral William Leahy argued against it, telling Roosevelt that it "would violate every Christian ethic I have ever heard of and all known laws of war. It would be an attack on the noncombatant population of the enemy."

Japanese rice was never sprayed. The war ended before Roosevelt made any decision. Apparently, JAG didn't answer the legality question until 1945, concluding that the use of these compounds wouldn't violate the protocol, as long as they weren't toxic. That opinion has never been validated in any world forum.

The Chemical Corps was also looking for defoliants capable of destroying the Asian jungle in order to reveal enemy hiding places and ease the construction of new bases. One officer later explained, "There was a great deal of interest at that time in destroying vegetation in the South Pacific Theater, and the principal means available was high explosives. I have forgotten how many millions of tons of high explosives were required to destroy the vegetation on some of those Pacific islands. We were asked to investigate...