Joseph A Castellano. American Scientist. Volume 96, Issue 6. Nov/Dec 2008.
From 1962 to 1965, the U.S. government funded a number of classified research projects in advanced rocket fuels. In those Cold War years, both the United States and the Soviet Union were developing Inter-Continental Ballistic Missiles (ICBMs) with longer ranges and higher payloads than earlier versions. But the research into and development of a number of potential propellante that took place during that period has largely been forgotten. An intriguing part of the story was the Soviet Union’s espionage efforts to obtain information on America’s secret solid rocket-fuel development program. I was a part of one of those programs, and I had personal experiences that led me to find out more about one particular spying case that is now largely buried in obscurity.
In May 2007, 1 was browsing through my local bookstore when I ran across Spy Handler: Memoir of a KGB Officer, written by Victor Cherkashin. About halfway through this autobiography, a passage mentioned a Soviet agent named Anatoly Kotlobai, an American scientist of Russian descent who provided the KGB (the Soviet Union’s equivalent of the Central Intelligence Agency or CIA) with samples of formulas for solid rocket fuel in the 1960s. For me, this was an astonishing revelation. Although the spelling of the name was slightly different, this person appeared to be the same one I had worked with for more than two years and who I believed was arrested for spying by the FBI in 1964. Since that time, I have often wondered whether he was actually guilty of espionage. Did he ever stand trial? Was he convicted or exonerated? Cherkashin’s book finally shed some light on this fascinating story and prompted my research into science and espionage during the Cold War.
The Race Begins
In the spring of 1962, 1 began working as a research chemist with the Reaction Motors Division (RMD) of Thiokol Chemical Company in Denville, New Jersey, a small town in the western part of the state. The parent company was building the Minuteman ICBM, and RMD was primarily engaged in the business of fabricating a small rocket engine known as the Bullpup. This engine was used by the U.S. military in the air-to-ground missiles that were being deployed in the rapidly escalating Vietnam War.
Another part of RMD’s business was classified research for various military agencies who were seeking new, more powerful and more efficient rocket propellante. I worked in the group that did this research. Our mandate was to synthesize organic compounds with a large number of difluoramino (NF2) groups. We experimented with such exotic materials as difluoramine (HNF2), tetrafluorohydrazine (N2F4) and perfluoroguanidine (a compound of carbon, nitrogen and fluorine, abbreviated PFG). The idea was that the higher the number of these difluoramino groups per molecule, the more “energetic” the material became. The NF2 groups acted much like nitro (NO2) groups do in explosives such as trinitrotoluene, or TNT. However, because the difluoramino group has a higher density than the nitro group, the compounds had the prospect of being superior propellant oxidizers in solid formulations. Other companies and military agencies were also working with these materials under classified contracts.
The push for improved technology was largely driven by the desire to surpass Soviet missile technology and overcome what many Americans saw as a growing “missile gap.” In October 1957 the Soviet Union successfully launched Sputnik, the world’s first human-made orbiting satellite, surprising American policymakers and the military establishment as well as the general public.
Shortly after Sputnik’s launch, a board of civilian consultants told CIA Director Allen Dulles that the U.S. trailed the Soviets in this vital field by some “two to three years.” The group further warned that the Soviet Union could deploy a dozen missiles capable of striking the United States by the end of 1958. Within two years, Congressional hearings concerning the “missile gap” provided the public with a view into the superpower race for rockets, and they offered the Air Force an opportunity to promote expensive new missile systems.
Estimates of Soviet capabilities varied widely through those years. The Kremlin obviously did not publicize its military plans and the claims it made were rarely trusted in the West. In 1958 the CIA informed President Eisenhower that the Soviets might have as many as 500 ICBMs by 1961. However, flights by high-altitude spy planes such as the U-2 in 1959 and 1960 gave lower estimates of Soviet capabilities, although no one could know for certain the true measure of Soviet missile strength. Nevertheless, the “missile gap” became an important political issue in the 1960 presidential election and was a major factor in John F Kennedy’s defeat of Richard M. Nixon, as Kennedy successfully played up the gap in his campaign speeches. But much like the intelligence in 2002 on Iraq’s “weapons of mass destruction,” the government’s information on the Soviet missile strength in 1960 was flawed; the missile gap was a myth.
Searching for Stability
Over the first few months of my employment at RMD, I learned a great deal about the work going on at Thiokof as well as the goals of the ICBM program. Early rocket designs used liquid fuels that required one cryogenic tank filled with liquid hydrogen and another with liquid oxygen. The two liquids were fed into a combustion chamber and the mixture was ignited by an electric signal. The Saturn V booster that sent astronauts to the Moon used this system. Another type of liquid-fueled rocket design used a “reaction motor,” where a liquid fuel (such as hydrazine) and an oxidizer (such as nitrogen tetroxide) immediately combusted without any igniter. Liquid- fueled motors could be turned off simply by shutting down the supply of the two liquids. A solid-fueled rocket, by comparison, uses a mixture of solid oxidizer and fuel, precast into the shape of the rocket and enclosed in its casing. When ignited at the nose of the rocket, the fuel continues to burn from top to bottom, and from the center outwards, until all the fuel is depleted. Once ignition begins in a solid-fueled rocket, it cannot be turned off. However, a solid-fueled rocket is ready to go at a moment’s notice, unlike a liquid-fueled ICBM, whose fuel requires extensive preparation before launch.
The Minuteman was a 3-stage, solidfueled strategic guided missile designed to be silo launched, from below ground, at surface targets. The 60-foot-long, 5.5-foot-diameter missile had a range of approximately 5,500 nautical miles. Minuteman also possessed an all-inertial guidance system, a self-contained unit that automatically kept track of position, velocity and attitude, and used the information to direct the missile’s course. And Minuteman could be fired from widely dispersed undergroundsilo launchers; the concept of a dispersed launch had originated just a few years before. Minuteman was the first solidfueled missile to enter service, giving it a large margin of improvement over the earlier Titan ? liquid-fueled ICBM. Solid fuel gave Minuteman a much higher reliability rate, easier maintenance and a longer storage time, and it could be launched within seconds of the launch keys being activated.
In September 1959 the Air Force successfully launched a Minuteman first-stage motor directly from an underground silo. Some 17 months later, a Minuteman containing all three stages and operational subsystems was launched from the Air Force Missile Test Center in Rorida. The missile performed flawlessly and after a flight of 4,600 miles its reentry vehicle landed within a designated impact zone. Based on this achievement, the Department of Defense formally accelerated the Minuteman program and gave it the same development priority as the Atlas and Titan ICBM programs. Early in 1962, a complete Minuteman was launched from a silo at the Air Force Test Facility at Vandenberg Air Force Base in California. The missile recorded a successful flight of 3,000 miles. As a result, the Minuteman I, also known as the LGM-30A, was slated to enter U.S. Air Force service. It would carry a single nuclear warhead, called a W59, with a yield of 1 megaton, equivalent to the explosive force of one million tons of TNT.
Larger follow-on versions to Minuteman I were already on the drawing board. Thiokol’s engine was designed to be incorporated into the first stage of Minuteman ?, the LGM-30F, which would carry one 1.2 megaton nuclear warhead, called a W56. The Minuteman II also was being designed to have a range of 7,000 nautical miles with an improved second stage and a dramatically improved guidance system, and was to be the first missile equipped with microelectronic circuitry, rather than bulky, individual electronic components.
At about the same time as the solidfueled Minuteman II was being developed in the U.S., the Soviet Union was working on the liquid-fueled UR-250 ICBM. Although the Soviets believed they were still ahead of the United States in the development of advanced ICBMs, they were concerned that the Americans were catching up quickly. Since the Soviet Union’s rockets used liquid propellant (nitrogen tetroxide, N2O4, for the oxidizer and unsymmetrical dimethylhydrazine, CH8N2, for the fuel), they had a strong desire to determine the major advances Americans had made in solidfuel development. Consequently, one goal of their espionage program was to obtain such information.
The War Years
Perhaps the most intriguing aspect of the work at RMD was that it was government classified, so we could not talk about the work outside the facility. At that time, the U.S. Naval Research Laboratory in Washington, the sponsoring agency, was expecting to use some of these materials as oxidizers in combination with aluminum or boron for solidpropellant formulations. Consequently, security was a major issue. For example, all briefcases were searched by security guards when anyone carrying one entered through the gate marking the entrance to the laboratory facilities. The same was true at the exit of the faculty. Non-employees would also be subjected to a body search.
Taking any document marked “classified” or “secret” out of the facility was strictly prohibited, so taking work home was quite limited. In addition, all file cabinets had special locking systems with combination locks. All documents had to be stored in these cabinets at the end of the shift. Despite all this security, information sometimes leaked out; it’s impossible to lock up someone’s brain.
There were more than 50 people working in the research department at that time. I worked in the organic chemistry synthesis group headed by Donald Perry. Our group also included a Russian immigrant who spelled his name Anatole P. Kotloby; he preferred to be called Paul. Kotloby had been captured as a young man by the Germans in World War ?. During the two years we worked together, he related some of the events from his past, including a description of the living conditions in German camps where Soviet and Polish prisoners were incarcerated during the war. These stories were confirmed for me later in the 1960s when I worked at RCA Laboratories in Princeton, New Jersey, where I became friends with Lucian “Luc” Barton (his real name was Lucjan Bartoszewicz), a Polish immigrant, who described to me in vivid detail his similar experiences in a German prisoner-of-war camp.
Kotloby was serving in the Soviet Red Army during Hitler’s “Operation Barbarossa,” an invasion that was aimed to overthrow the Communist regime of Joseph Stalin. The Soviet armies had been decimated by Stalin’s prewar purges of “enemies of the people,” and their ranks crumbled rapidly in the face of the Nazi attack. In the first few months of the war, many Soviet units were trapped by a huge German encirclement, resulting in a mass surrender. The prisoners were forced to walk more than 100 miles to a detention camp. Because of the physical exertion of the march and the lack of adequate food and water, many prisoners of war collapsed. The Sixth German Army had been given orders that all prisoners of war who broke down were to be executed.
When the prisoners arrived at the camp, they were appalled to see that there was no housing. The camp was simply an open area fenced off with barbed wire. The prisoners had to lie in the hot sun or sit in the mud during the rainy season. Disease epidemics decimated the camps. Prisoners were often subjected to beatings and abuse by the guards; they spent weeks without food or shelter. Daily rations amounted to only one-fourth of what a normal person needs to survive. Eventually, some 20,000 Soviet POWs were loaded on railway cars and sent by train to Germany, where they were imprisoned in concentration camps.
At first, the Soviet prisoners were held in barbed-wire enclosures out in the open, where many of them died. Because the Soviet Union had not signed the Geneva Convention, the Germans believed they were not required by international law to treat Russian POWs humanely. Huts to accommodate the prisoners were only provided over a period of time, and in most cases the prisoners themselves had to construct them. By the middle of January 1942, hundreds of prisoners were dying every day. Many died of dysentery, but most perished in an epidemic of typhus, also called spotted fever.
Amid these horrendous conditions, Kotloby somehow managed to survive his incarceration. As he told these stories to me and others at Thiokol, more than 20 years later, he was remarkably matter-of-fact. Because he had no obvious scars or disabilities, and as he was the first person I’d encountered who had lived through such an ordeal, it was hard to imagine him in such dire circumstances.
In April 1945, British units liberated the camps. Kotloby probably planned to return to Russia and resume his life as a Soviet citizen. However, the prisoners soon learned from the British officers that many surviving Soviet POWs repatriated to the USSR were arrested on suspicion of collaboration with the Germans, and almost without exception, they were sentenced to long terms in Soviet prisons known as Gulags. Although I don’t recall his mentioning it, Kotloby reportedly worked as a translator for the Germans and thus feared that he might suffer a similar fate. And so, like many other refugees of World War II, Kotloby emigrated to the United States. Eventually he settled in New Jersey where he earned a Bachelor of Science degree in chemistry. He passed all FBI security and background checks when he began working at RMD, several years before I started there.
The work Kotloby and I were doing at RMD was exciting, but sometimes dangerous, because many of these materials were highly shock sensitive and had the nasty habit of exploding with little provocation. For example, once I was using very sophisticated distillation equipment to separate some difluoramino compounds when the entire apparatus exploded. Fortunately, the shielding prevented me or anyone else from being hurt. Another time, a technician was simply turning a valve when the friction of the barrel rotating in its sleeve was enough to create an explosion. He received serious burns on his hand and arm, but he fully recovered. Yet another incident involved the accidental release of beryllium hydride, a highly toxic gas. Even though the laboratory was specially designed and had numerous safeguards, a fire broke out, causing some of the toxic gas to leak into the building’s air handling system. We were not permitted to enter the laboratories until the next day.
The research was leading-edge synthetic organic chemistry, and this laboratory was staffed with highly qualified chemists, physicists and engineers. Also, the latest and finest equipment was available to us. Because of the dangerous nature of the materials being developed, we worked behind thick Plexiglas shields and used remote robotic arms called mini-manipulators to handle toxic, explosive materials.
Kotloby’s research involved the preparation of highly energetic materials for use in solid rocket-propellant formulations. These substances were made by chemical reactions between N2F4 and various organic compounds. Organic compounds, by definition, are composed of molecules having carbon and hydrogen atoms, although they can contain oxygen, nitrogen and other atoms as well. For a short time, Kotloby and I carried out reactions with N2F4 and a series of compounds that were used to prepare urethanes. These compounds contained many dmuoramino groups to give the material the properties needed for propellant formulations.
These reactions were carried out in a special exhaust hood lined with quarter-inch steel plates. For the reactions of N2F4 with various compounds under high pressure and temperature, we used small stainless steel cylinders with a capacity of about 150 milliliters. These cylinders were called “bombs,” and I was never quite sure if the name related to their appearance, which resembled a hand grenade, or to their occasional tendency to explode unexpectedly.
All of the tubes and valves of the vacuum system in this hood were made of stainless steel. The hood also had a small, circular window made of half-inch-thick Plexiglas so that the bomb’s temperature and pressure could be observed during the process. Kotloby had designed and built this setup, so he became the resident expert on this technique. In fact, he taught me the procedures for carrying out high-pressure reactions between N2F4 and various other chemicals in these bombs. Reports on these experiments and others have now been declassified, and some were subsequently published in the open literature.
In 1963, Kotloby and a technician in our group, Warren Weiting, began to synthesize a whole series of compounds that had three NF2 groups attached to one carbon atom by reacting PFG with alcohols. This was an important development because it meant that one could make compounds with a larger number of NF2 groups than was possible by using N2F4 alone. Thanks to Robert D. Chapman; a scientist who has worked in rocket-fuel research for many years using these types of materials at the U.S. Naval Air Warfare Center Weapons Division in China Lake, California, I discovered that the unclassified reports are still available in government archives. Some of these compounds were highly shock sensitive. One time a microliter syringe exploded in Weiting’s hand as he injected one of the compounds into a gas Chromatograph. Fortunately, he was not injured. Apparently, friction created by movement of the syringe barrel was enough to set it off.
Owing to the extreme shock sensitivity of these compounds, it was necessary that all work with these materials be carried out behind barricades outfitted with remote-control equipment. Considerable effort had been devoted to the modification of an outside barricade laboratory for conducting experiments with PFG. The small, remote laboratory, located some 75 feet behind the main building, was constructed of plywoodcovered half-inch steel with a working area that measured about 7 feet by 8 feet. The building also had a separate control room about the same size. The roof of the building was made of a light material and only loosely attached to the walls to prevent pressure buildup in the event of an explosion. Because even small amounts of oxygen from the air could react explosively with PFG, the reactions had to be carried out in a “vacuum rack” system consisting of a matrix of glass and stainless steel tubes connected by numerous valves. Manipulation of these valves on the vacuum line and certain other necessary operations were done remotely from the control room by use of a mechanical manipulator arm. A half-inch-thick plastic-laminate safety window permitted observation of the entire working area.
Crude PFG was stored in a tank outside the barricade lab in a specially constructed temperature-controlled housing. From this tank, a remote-controlled valve was opened to enable measured amounts of crude PFG to enter the vacuum system and condense into a glass trap that was cooled by liquid nitrogen to -196 degrees Celsius, then purified at -110 degrees.
On one occasion, when Weiting was canying out this process, the entire glass trap exploded violently. He jumped back in spite of the fact that he was protected by the thick plastic shield. The explosion completely destroyed all the of the glass sections of the vacuum rack. Weiting was clearly shaken to see such a violent explosion occur right before his eyes.
Kotloby did not seem conscious of the fact that such incidents made his coworkers sensitive. He was in the habit of testing the materials he made for shock sensitivity by hammering a few milligrams of the compound on a solid metal anvil. Every now and then we would hear three or four hammer strikes followed by a sound that resembled an exploding firecracker as the material ignited. It was unnerving to most of us because we didn’t know whether it might be a rogue explosion in which someone was injured. Consequently, whenever this happened, people from adjoining labs would run in to see if anyone was hurt. Eventually, Kotloby would announce loudly that he was “testing.” Still, others did not appreciate his performing this annoying and rather inaccurate test.
One day in the fall of 1964, FBI agents met Kotloby at the front gate and detained him. I didn’t see him detained, but several FBI agents came into our lab that same morning and asked me to point out Kotloby’s desk and file cabinet. The agents proceeded to examine his notebooks, his papers and all of his personal effects, then left with all the material, saying nothing to any of us. We never saw Kotloby again and never received any official word about what he was accused of doing. It was as though he had never existed. Kotloby’s habits had made him relatively unpopular, and he was something of a loner, so inevitably some of our coworkers began to say that they had always suspected him of being a spy. Rumor had it that he was passing classified information to the Soviets at a small bookstore in Manhattan, but these were unconfirmed reports. None of us ever found out if he was actually guilty of espionage.
I left the company in June of 1965 and learned nothing more about the incident until reading Spy Handler, in which Cherkashin describes how his colleague, Oleg Kalugin, recruited one Anatoly Kotlobai as an agent for the KGB. The KGB identified Kotlobai by the pseudonym “Cook,” presumably because he was a chemist. Kalugin details some of his encounters with Cook in his own book about his 32 years in intelligence and espionage against the U.S.
Kalugin became one of the first Soviet Fulbright exchange students at Columbia University after graduating from the Foreign Language Institute in 1958. Assigned to New York soon after, he worked undercover as a Radio Moscow correspondent reporting on the United Nations. About one year later, Kalugin moved to Washington, DC, where he worked for Boris Solomatin, known as the “rezident,” the name used to identify the head of the KGB’s local office. As a press officer, Kalugin circulated in the highest journalistic and political circles in the nation’s capítol. He regularly met with columnists Walter Lippmann and Joseph Kraft as well as Robert Kennedy and William Fulbright, along with many other prominent Washington insiders. According to Cherkashin, his news reports about the U.S. were fascinating.
Shortly after his arrival in Washington, Kalugin recruited Cook, his first agent, who provided the KGB with formulas for the materials that he worked on at Thiokol for use in solid rocket fuel. According to both Cherkashin and Kalugin, the FBI soon came to suspect Cook and put him under surveillance. After he was detained and questioned by the FBI on that day in 1964, Cook was released because the FBI did not have enough evidence to hold him. Fearing that his espionage activities would be discovered, agent Cook, along with his Chinese-born wife, an avowed Maoist, boarded an Air France flight to Moscow before they could be apprehended.
Although Kalugin describes Cook as an orthodox communist, Cook didn’t enjoy life in Russia and began openly criticizing the “workers’ paradise.” His complaints weren’t well received and soon a division of the KGB launched an investigation into charges that the scientist was actually a double agent working for the CIA. The KGB could not come up with compelling evidence, however, so they entrapped Cook in a currency-exchange sting operation. He was arrested and sentenced to eight years in prison.
Convinced Cook was not a “dangle,” a CIA double agent, Kalugin took his concerns to Yuri Andropov, then head of the KGB. Although Kalugin was close friends with Andropov, he could not convince the KGB chief of Cook’s innocence. Nevertheless, Andropov allowed Kalugin to interrogate the prisoner. When Kalugin met the agent he recruited in the 1960s, Cook was livid. He cursed Kalugin, saying he regretted the day the two had met. Kalugin left feeling even more convinced that the man had nothing to do with U.S. intelligence.
Kalugin returned to Moscow in 1970 after American journalist Jack Anderson exposed him as a KGB officer. Solomatin recommended Kalugin for work in another division, so he was soon appointed head of the counterintelligence branch and promoted to general, the youngest in KGB history. Kalugin retired as a major general from the KGB in 1990 and served in parliament for several years before moving to the U.S. and writing his autobiography. He now teaches at the Centre for Counterintelligence and Security Studies in Alexandria, Virginia, and he recently became a U.S. citizen.
As for Cook, nothing more is said about him in Cherkashin’s book, but Kalugin, whom I spoke to personally, said Cook remained in Russia after he was released from prison. In fact, Kalugin visited with Cook and his wife in Moscow several years ago. Kalugin also confirmed that the Anatoly Kotlobai described in Cherkashin’s book and the Anatole Kotloby whom I worked with 44 years ago are indeed one and the same person. There are no accounts of what Cook and his wife did between the time he got out of prison and now.
The chemical reactions of PFG with alcohols that Kotloby and others developed were never published in the open literature by researchers from Thiokol because the work was not declassified until after most of the researchers left the company. However, papers reporting on this work were published by researchers from other U.S. organizations in 1967, as well as by A. V. Fokin and his colleagues in the Soviet Union in 1969. Based on my own experience publishing papers taken from classified research during the 1960s, the latter paper undoubtedly represents work done several years before. I have not been able to determine whether or not the Soviet scientists independently initiated the work, or if it was influenced by Kotloby’s leaked information.
Taking a Turn
In the end, the Soviet espionage activities that took place during those years on American rocket-fuel research made no impact on the space programs of either the U.S. or the Soviet Union. Both sides continued to use other materials and the research work on the difluoramino compounds was declassified a few years later. Almost all difluoramine derivatives at that time had inadequate stability, insensitivity or physical properties to serve as replacements for other materials, so they never became practical as rocket propellants for deployed weapons systems.
In the 1980s, there was a resurgence of interest in difluoramino compounds and work has continued since then at the U.S. Naval Air Warfare Center Weapons Division in China Lake, California, aimed at producing energetic materials for weapons systems. However, the fascinating research on organic compounds that contain the difluoramino group was never seriously extended to wider applications. This is unfortunate because NF2 could be a possible building block to synthesize new biologically active molecules. The use of fluorine in biologically active materials is continually under investigation. In fact, the drugs Lipitor (for high cholesterol), Advair Diskus (for asthma) and Prevacid (for gastric reflux) – three of the top ten pharmaceuticals sold in 2007 – contain one or more fluorine atoms. And for more than 40 years, 5-fluorouracil has been one of the leading drugs used in cancer chemotherapy, where it operates by altering the synthesis of DNA in cancer cells leading to apoptosis, or biochemically programmed cell death.
The strong electron-withdrawing nature of the difluoramino group might make it a candidate for use in anti-cancer drugs or other biologically active materials. Although compounds that contain many dmuoramino groups are certainly shock sensitive, a number of very stable difluoramino compounds were prepared in Thiokol’s RMD laboratories in the 1960s. Starting with tetrafluorohydrazine, a colorless gas that readily dissociates into free radicals, many types of diflouramino-containing compounds can be synthesized. Coupling these substances with other free radicals can lead to molecules that have one difluoramino group and are very stable.
Compounds with two difluoramino groups attached to the same carbon atom (called geminai bis-difluoramino compounds) can be produced by the reaction between difluoramine and ketones, which contain carbon atoms doublebonded to oxygens. Vicinal bis-difluoramines, which have dmuorairiino groups attached to adjacent carbon atoms, can be prepared by the addition of tetrafluorohydrazine to olefins, molecules that contain carbons double-bonded to each other. The resulting dmuoramines can also undergo rapid dehydrofluorination (where hydrogen atoms in a molecule are replaced with fluorine) with a variety of bases to form N-fluorimines, which may also be biologically active.
Attaching a ctifluoramino group to a benzene ring of carbon atoms to form aromatic difluoramino compounds is more challenging. Aromatic compounds are unsaturated, meaning they have double bonds and therefore the ability to link to new atoms, but they are less reactive than expected. The direct fluorination of weakly basic aromatic amines in liquid hydrogen fluoride has been reported to lead to the formation of dmuoramino benzene derivatives. This technique may be useful to synthesize purine and pyrimidine bases containing NF2 or NF groups for possible use in cancer chemotherapy. These nitrogen-laden bases are a large part of DNA, RNA and other biologically important compounds. The concept of chemotherapy is to introduce compounds into a cancer-cell forming environment that mimic the chemical behavior of the natural bases. But because the introduced bases contain “rogue” atoms, such as fluorine, the compounds result in the formation of distorted DNA, which quickly results in the death of the cancer cells. This process also affects normal cells, so a vibrant area of research is making chemotherapy drugs that target only cancerous cells.
Science, like human nature, isn’t always neat and linear, and can go in unanticipated directions. It is ironic that compounds originally designed for such destructive purposes may have life-saving health benefits. The information that the U.S. and the Soviet Union worked so hard to keep secret could now be important to share widely for the medical well-being of a large number of people. Of course, scientists would have to tackle new research on these compounds to determine which ones might be stable, functional and targeted to specific cancer-cell types. I hope that on reading about the checkered past of this largely forgotten field, adventurous scientists will consider these fascinating compounds for further investigation.