The Secret History of Diplomats and Invisible Weapons

The alleged use of a “sound weapon” against U.S. Embassy officials in Cuba harks back to a Cold War medical mystery.


This month, the State Department revealed that American diplomats based in Cuba have suffered from possible hearing damage. Since then, hysteria over “sonic weapons” has exploded, and the number of diplomats said to be experiencing health effects, which may include brain damage, has also now increased. “We hold the Cuban authorities responsible for finding out who is carrying out these health attacks,” Secretary of State Rex Tillerson said. The device, or possible weapon, that was used to cause these effects apparently made no sound. Yet there is no credible evidence that such a non-audible device could cause the damage described. It turns out, this isn’t the first time the U.S. government suspected a foreign country of targeting its diplomats with a secret, invisible weapon.

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This month, the State Department revealed that American diplomats based in Cuba have suffered from possible hearing damage. Since then, hysteria over “sonic weapons” has exploded, and the number of diplomats said to be experiencing health effects, which may include brain damage, has also now increased. “We hold the Cuban authorities responsible for finding out who is carrying out these health attacks,” Secretary of State Rex Tillerson said. The device, or possible weapon, that was used to cause these effects apparently made no sound. Yet there is no credible evidence that such a non-audible device could cause the damage described. It turns out, this isn’t the first time the U.S. government suspected a foreign country of targeting its diplomats with a secret, invisible weapon.

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In 1965, medical workers began showing up at the American embassy in Moscow, drawing blood from the employees inside. The American diplomats were told that doctors were looking for possible exposure to a new type of virus, something not unexpected in a country known for its frigid winters.

It was all a lie. The Moscow Viral Study, as it was called, was the cover story for the American government’s top secret investigation into the effects of microwave radiation on humans. The Soviets, it turned out, were bombarding the embassy in Moscow with low-level microwaves. The “Moscow Signal,” as officials in Washington called the radiation, was too low to do any obvious harm to the people in the building. At five microwatts per square centimeter, the signal was well below the threshold needed to heat things, as a microwave oven does. Yet it was also a hundred times more powerful than the Soviets’ maximum exposure standards, which were much more stringent than those of the United States. That was cause for alarm.

The intelligence community was worried that the Soviets knew something about non-ionizing radiation that the United States did not. With research into the effects of low-level radiation still in its infancy, one of the first theories forwarded by the CIA was that the Soviets were trying to influence the behavior or mental state of American diplomats, or even control their minds. The United States wanted to figure out what was going on without tipping off the Soviets that they knew about the irradiation, and so the diplomats working in the embassy—and being exposed daily to the radiation—were kept in the dark. The State Department was responsible for looking at biological changes associated with microwaves, and the Defense Advanced Research Projects, a division of the Pentagon, was assigned to look at the possible behavioral effects of microwaves.

In October 1965, Richard Cesaro, the DARPA official in charge of the project, addressed a secret memo to the agency’s director, Charles Herzfeld, explaining the justification for this new research effort. The White House had charged the State Department, the CIA, and the Pentagon to investigate the microwave assault in secret. The State Department was the lead on the program, code-named TUMS, and DARPA’s responsibility, Cesaro explained, was “to initiate a selective portion of the overall program concerned with one of the potential threats, that of radiation effects on man.”

Thus was born DARPA Program Plan 562, better known by its code name, Project Pandora, an exploration of the behavioral effects of microwaves and one of the more bizarre episodes in the history of Cold War science.

With the passage of time, the government’s concerns about microwave-induced mind control might sound like something born of the worst sort of Cold War paranoia—the sort of thing easily parodied as a tin-foil-hat conspiracy—but set in the landscape of the 1960s, it seemed a plausible concern. The discovery of the Moscow Signal came amid a flurry of American and Soviet research reports on the possible biological effects of low-level microwave radiation. Anecdotal reports of fatigue and confusion fueled theories that microwaves could be used as a weapon for behavior modification, or even mind control.

One theory that officials floated was the Soviet Union might be using microwaves to influence the behavior of embassy workers, perhaps to induce clerks to make mistakes on encrypted messages, allowing Soviet cryptographers to crack American codes. In fact, DARPA-sponsored translations of Russian-language research at the time indicated that the neurological effects of microwaves fascinated the Soviets, which American officials took as possible evidence that the Moscow Signal was some sort of weapon.

DARPA’s role in Pandora immediately evoked concerns among the few Pentagon scientists who were cleared to review the program. Bruno Augenstein, a German-born physicist who worked for the Defense Department, sent a top secret memo to Harold Brown and Gene Fubini, two of the Pentagon’s top technology officials, to let them know that DARPA was evaluating proposals looking at the neurological effects of microwaves. In his note, Augenstein alluded to “past unsavory history of experiments of this kind in this country, which has made a number of people rather leery of further experiments in this field,” likely a reference to the CIA’s infamous MKULTRA mind control experiments begun in the 1950s, in which agency officials tested the effects of LSD as a possible mind control agent on humans. Augenstein wrote that there did appear “to be some internal resistance in DARPA to the suggestion that DARPA proceed with these experiments, probably because there is a feeling that at one time it certainly attracted a number of crackpots.”

If the DARPA program was supposed to avoid the mistakes of prior scandals in human experimentation, then Cesaro was an inauspicious choice to lead Pandora. A propulsion expert, he had no apparent expertise in the biological sciences, but he relished running a top-secret project that had high-level attention from the White House and the CIA. He embraced the assignment with an enthusiasm that might have been admirable, had it not been quite so morbid. It soon became clear Cesaro’s primary interest was pushing forward with actual microwave weapons, rather than understanding the underlying biology.

To see if the Moscow Signal really affected human behavior, DARPA first started by testing microwave radiation on monkeys. Because Pandora was top secret, the primary research had to be run at government laboratories rather than at universities. The air force was assigned to provide electromagnetic equipment needed to generate the microwaves, and the Walter Reed Army Institute of Research was responsible for selecting the monkeys and running the experiments. The initial tests were designed to see how primates performed work-related tasks when exposed to radiation that matched the Moscow Signal, which was beaming every day at the men and women inside the American embassy in Moscow.

The test protocol involved training the monkeys to press certain levers in response to signals. If the monkeys pressed the lever correctly, they would receive a reward of food, “much as embassy employees might be rewarded with a dry martini at the end of the day,” wrote the columnist Jack Anderson. Researchers would then measure whether the monkeys performed worse when subjected to the Moscow Signal, compared with when there was no radiation.

By December 1965, Cesaro was already enthusing over the results. The normal process for accepting any new, significant scientific phenomenon would have involved submission of the results for peer review, publication in a respected journal, and eventually replication by an independent group. Pandora, on the other hand, operated in the world of classified science, where results were conveyed not by the researchers conducting the experiments but by the manager in charge, in this case Cesaro.

In December 1966, Cesaro reported that the first monkey involved in the tests had demonstrated “two repetitive, complete slowdowns and stoppages” as a result of exposure to the Moscow Signal. “There is no question that penetration of the central nervous system has been achieved, either directly or indirectly into that portion of the brain concerned with the changes in the work functions and the effects observed,” Cesaro wrote.

The radiation results were so convincing to him that he recommended the Pentagon immediately start to investigate “potential weapon applications.” He initiated a new phase of Pandora intended to move toward human testing, taking the DARPA program dangerously close to the very work that Augenstein, the Pentagon scientist, had warned of. Cesaro also wanted to make Pandora even more secretive than it had been previously. “The extremely sensitive nature of the results obtained to date, and their impact on National Security, has resulted in establishing a special access category for all data results and analysis, under codename Bizarre,” he wrote. Bizarre, as it turns out, was an appropriate name for the project, because at this point the number of monkeys involved in the testing stood at one.

Initially, the Pandora scientific review committee seemed to go along with Cesaro’s enthusiastic proposal to move directly to human testing. The committee even suggested recruiting human subjects from Fort Detrick, Maryland, home to the army’s biological research program (the conscripts assigned to Fort Detrick have been a continuous source of human subjects for Defense Department research for decades; subjects there have been exposed to everything from yellow fever to hallucinogenic drugs). In minutes from a May 12, 1969, meeting to discuss human testing, the Pandora scientific committee discussed plans to move forward with eight human subjects. The human subjects would be exposed to the Moscow Signal and then given a full battery of medical and psychological tests.

The committee was aware of the potential for a conflict of interest involved in classified human testing; the idea of informed consent becomes hazy when the subjects are not even aware of the true purpose of the test. To address this problematic issue, the committee recommended having medical personnel on hand to assure the “medical well being” of the subjects. Yet even those medical personnel would not be told the reason for the testing and would instead be given a cover story. Humanely, at least, the committee did recommend “gonadal protection be provided” to the male test subjects.

Fortunately for the would-be recruits and their gonads, the human tests were never pursued. The committee’s views on Pandora quickly began to change as they reviewed the actual data, which eventually included more primates and additional testing. The scientific committee’s minutes, declassified and released years later, demonstrate increasing doubts about the testing protocol, in particular the lack of controls used in testing the monkeys. Among the concerns was that there was never a solid baseline established to compare how the monkeys’ performance allegedly degraded after exposure to radiation, the members noted. In other words, it was never established how well monkeys performed the tasks during a test period when not exposed to any periodic bouts of radiation.

While Pandora never progressed to testing on humans, it did look at the effects of occupational radiation exposure on humans. One experimental protocol, called Big Boy, examined sailors on the USS Saratoga, comparing those who worked above deck, and were exposed to radiation from the radar, to those who worked below deck (the sailors were not told that they were part of a human radiation study; an unspecified cover story was used). The conclusion was that there were no psychological or physical effects as a result of exposure to low-level microwave radiation.

In 1968, Joseph Sharp, the lead Pandora researcher at Walter Reed, left the program. Major James McIlwain, a medical doctor who had been drafted into the army, was selected to replace him. It took almost a year before McIlwain was cleared for Project Pandora, but once that happened, he got to work on a rigorous review of the data, poring over the computer printouts detailing each animal’s behavior. Within a year, McIlwain completed the statistical analysis, and what he found was not encouraging for the prospects of microwave mind control weapons. The basic question, he recalled in an interview years later, was whether it was more likely that the animal would stop working when the radiation was on compared with when it was off. “The answer to that was no,” he said. The Pandora scientific review committee agreed, concluding, “If there is an effect of the signal utilized to date on behavior and/or biological functions, it is too subtle or insignificant to be evident.” In other words, microwaves could not be used for mind control.

By 1969, Stephen Lukasik, then the deputy director of DARPA, had some serious doubts about Cesaro, whom he regarded as a serial liar. The impresario of DARPA’s black programs acted as if he reported to no one, alluding to orders from high-level intelligence agencies but refusing to provide any specific information. “He was all over the place, cloaked in special access programs,” Lukasik said, a reference to highly classified national security programs.

Pandora, the mind control project, was particularly worrisome. At that point, the research had been going on for almost five years, and millions of dollars had been spent for construction of a new microwave laboratory. Lukasik asked Sam Koslov, a former DARPA official, to review the Pandora file and let him know what he thought. Koslov was an old hand at intelligence projects and less likely to be snowed by claims of secrecy and overwrought concerns about the potential for Soviet exotic weapons. Koslov, then at the Rand Corporation, reviewed the materials and discussed the results with McIlwain, at Walter Reed, and reported back to Lukasik in November 1969.

Like other review committee members, Koslov criticized the original experiments for having almost no baseline and noted the experimental procedure changed over time. Also, if the question was whether a modulated microwave beam, such as the Moscow Signal, was causing deleterious effects, why was it never measured against a continuous wave? he asked. Simply zapping monkeys with the Moscow Signal was an entirely wrong approach, if the goal was to understand whether the effects were associated with a specific signal. “One should start with an examination of various basic wave forms and then the combinations resulting in possible intermodulations and demodulations by biological tissue,” Koslov wrote.

Koslov also rightfully questioned whether the entire program truly needed to be secret.

One could much better run a more open program that looked at the health effects of microwaves generally and then have a secret program looking at technology or weapons, if it was warranted, he argued. “In brief, I am forced to conclude that the data do not present any evidence of a behavioral change due to the presence of the special signal within the limits of any reasonable scientific criteria,” Koslov wrote to Lukasik.

In 1969, DARPA ended its support for Pandora, and the remaining work was transferred to Walter Reed. A couple years later, Lukasik fired Cesaro for “general dishonesty.”

By the end of the 1960s, the intelligence community concluded that the Soviets were using the pulsed radiation to activate listening bugs concealed in the embassy’s walls, and not to control diplomats’ minds.

Yet concerns about the Moscow Signal lingered even after the scientific testing ended, though mind control was generally ruled out. A State Department doctor in charge of the blood tests, Cecil Jacobson, asserted that there had been some chromosomal changes, but none of the scientific reviews of his work seemed to back his view. Jacobson achieved infamy in later years, not for the Moscow Signal, but for fraud related to his fertility work. Among other misdeeds, he was sent to prison for impregnating possibly dozens of unsuspecting patients with his own sperm, rather than that of screened anonymous donors as they were expecting.

Richard Cesaro never attained that level of personal notoriety, but he asserted, even after he retired, that the Moscow Signal remained an open question. “I look at it as still a major, serious, unsettled threat to the security of the United States,” he said, when interviewed about it nearly two decades later. “If you really make the breakthrough, you’ve got something better than any bomb ever built, because when you finally come down the line you’re talking about controlling people’s minds.”

Perhaps, but Pandora resonated for years as the secrecy surrounding the project generated public paranoia and distrust of government research on radiation safety. Project Pandora was often cited as proof that the government knew more about the health effects of electro- magnetic radiation than it was letting on. The government did finally inform embassy personnel in the 1970s about the microwave radiation, prompting, not surprisingly, a slew of lawsuits.

In the end, the government found that the best method for dealing with the incessant Moscow Signal was to build an aluminum screen to shield the building from microwaves. “The lesson learned,” Koslov later told a reporter, “is to treat your people as if they have some intelligence.”

This article is adapted from Sharon Weinberger’s book, The Imagineers of War: The Untold Story of DARPA, the Pentagon Agency that Changed the World.

Photo credit: Ed Schipul/Flickr

 Twitter: @weinbergersa

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