Operation Paperclip: The Secret Intelligence Program that Brought Nazi Scientists to America

by Annie Jacobsen

the Reich had first sterilized and then euthanized nearly its entire population of mentally ill persons, including tens of thousands of children, under the Law for the Prevention of Genetically Diseased Offspring. All across southern Germany, one German physician after the next admitted to Dr. Alexander his knowledge of the child euthanasia program.

In less than two years, many of the Nazi doctors chosen by Dr. Strughold would quietly begin their secret journeys to the United States.

John J. McCloy, the assistant secretary of war and chairman of SWNCC. John J. McCloy would become an especially significant player in Operation Paperclip starting in 1949.

“In 1945, in the aftermath of World War II, the U.S. Army Chemical Warfare Service decided to focus its research and development efforts on the German nerve agents, the technological challenges of which promised to ensure the organization’s survival through the period of postwar demobilization and declining military budgets.” Within several months of the German surrender, 530 tons of tabun nerve agent were shipped to the United States and used in Top Secret field tests. Requests to bring German chemists to the United States for weapons work quickly followed.

Kuhn had once been an internationally revered organic chemist, but rumor had it that he had become an ardent Nazi during the war. Kuhn won the Nobel Prize in Chemistry in 1938 but turned down accepting the award at the request of Hitler, who called it a Jewish prize.

Starting on June 1, 1945, these chemists would now be sent to a single location—a Top Secret interrogation facility outside Frankfurt. SHAEF was moving its headquarters from Versailles to Frankfurt and was to be dissolved in mid-July.

The structure that housed this new interrogation center was none other than Schloss Kransberg, or Kransberg Castle, Hermann Göring’s former Luftwaffe headquarters

The facility was the second-most classified interrogation center after Ashcan. Dustbin was self-contained inside its centuries-old stone walls, and, as it went at Ashcan, the prisoners here were free to roam the grounds and chat among themselves. Karl Brandt, Hitler’s doctor, organized morning gymnastics classes in the garden. Others played chess. Industrialists held lectures in the large banquet hall that Göring had once used as a casino. Speer took walks in the castle’s apple orchard, almost always alone by choice. Whereas Ashcan housed the Nazi high command, Dustbin had many Nazi scientists, doctors, and industrialists under guard. This included more than twenty chemists with IG Farben and at least six members of its board.

Farben chemist named Dr. Gerhard Schrader was captured and brought to Dustbin. Schrader was the man who created the nerve agent that had been found at Raubkammer, the Robbers’ Lair. The information Schrader had was among the most sought-after classified military intelligence in the world.

code name Preparation 9/91. Picking up where he’d left off with his work, he prepared a small amount of his new substance, diluting it to 1 in 200,000 units to see if it would kill lice clinging to leaves. He was stunned when his new creation killed 100 percent of the lice. Schrader repeated the experiment for his colleagues. They all agreed that Preparation 9/91 was a hundred times more lethal than anything anyone at the Leverkusen lab had ever worked with before.

a healthy ape was injected with a tiny amount of Preparation 9/91—just 1/10th of a milligram per kilo of body weight—the ape died in less than an hour. Next, Gross tested the substance on an ape inside an inhalation chamber. He watched this healthy ape die in sixteen minutes. Professor Gross told Dr. Schrader that his Preparation 9/91 was being sent to Berlin and that he should wait for further instruction on what action to take next.

The Reich’s Chemical Weapons Department began to evaluate Schrader’s Preparation 9/91 for its potential use in chemical warfare. In May 1937 Schrader was invited to Berlin to demonstrate how he’d synthesized Preparation 9/91. “Everyone was astounded,” Schrader told Tilley. This was the most promising chemical killer since the Germans invented mustard gas. Preparation 9/91 was classified Top Secret and given a code name: tabun gas. It came from the English word “taboo,” something prohibited or forbidden.

Karl Krauch, the head of Farben’s board of directors, began working with Hermann Göring on a longer-range plan to arm Germany with chemical weapons, ones that could eventually be dropped on the enemy from airplanes. In his report to Göring, Krauch called tabun “the weapon of superior intelligence and superior scientific-technological thinking.” The beauty in the nerve agent, Krauch told Göring, was that it could be “used against the enemy’s hinterland.” Göring agreed, adding that what he liked most about chemical weapons was that they terrified people. He responded to Krauch in writing, noting that the deadly effects of nerve agents like tabun gas could wreak “psychological havoc on civilian populations, driving them crazy with fear.”

Gendorf produced mustard gas on an industrial scale, and that Dyhernfurth produced tabun. Krauch also revealed a new piece of evidence. Dyhernfurth produced a second nerve agent, one that was even more potent than tabun, called sarin.

As the plant manager at Farben’s Buna factory at Auschwitz, Otto Ambros had been linked to atrocities including mass murder and slavery.

Otto Ambros had a razor-sharp mind. He was cunning and congenial, sly like a fox. He almost always wore a grin. The American war crimes prosecutor Josiah DuBois described him as having a “devilish friendliness” about him.

As a chemist, Ambros had a mind that was capable of pushing science into realms previously unexplored. Few men were as important to IG Farben during the war as Otto Ambros had been.

1940, Otto Ambros pored over maps of this region, called Upper Silesia, in search of a Buna factory site, he found what he was looking for. The production of synthetic rubber required four things: water, flat land, good railway connections, and an abundance of laborers. Auschwitz had all four. Three rivers met in Auschwitz, the Sola, the Vistula, and the Przemsza, with a water flow of 525,000 cubic feet per hour. The land was flat and sixty-five feet above the waterline, making it safe from floodwaters. The railway connections were sound. But most important was the labor issue. The concentration camp next door could provide an endless labor supply because the men were cheap and could be worked to death. For Farben, the use of slave labor could take the company to levels of economic prowess previously unexplored.

Erich Santo was assigned to serve as Otto Ambros’s construction foreman. “The concentration camp already existing with approximately 7000 prisoners is to be expanded,” Santo noted in his official company report. For Ambros, Farben’s arrangement with the SS regarding slave laborers remained vague; Ambros sought clarity.

Heinrich Himmler and Otto Ambros had known one another since grade school. Ambros could make Himmler see eye-to-eye with him on the benefits that Auschwitz offered to both Farben and the SS.

The SS agreed to provide Farben with one thousand slave workers immediately. That number, promised Himmler, could quickly rise to thirty thousand with demand. The relationship between Farben and the SS at Auschwitz was now cemented. Otto Ambros was the key to making the Buna factory a success. With his knowledge of synthetic rubber and his managerial experience—he also ran Farben’s secret nerve gas production facilities—there was no better man than Otto Ambros for the Auschwitz job.

the gas used to murder millions of people at Auschwitz and other concentration camps, Zyklon B, was a Farben product. Farben owned the patent on Zyklon B, and it was sold to the Reich by an IG Farben company.

In 1945, the Chemical Warfare Service was also in charge of the U.S. biological weapons program, the existence of which remained secret from the American public. The program was robust; if the atomic bomb failed to end the war in Japan, there were plans in motion to wage biological warfare against Japanese crops.

The Chemical Warfare Service saw enormous potential in making the Nazis’ biological weapons program its own and sought any scientific intelligence it could get. The man most wanted in this effort was Hitler’s top biological weapons expert, Dr. Kurt Blome.

Hitler, Blome said, did not approve of biological warfare and was kept in the dark as to specific plans. Himmler’s area of greatest fascination, said Blome, was bubonic plague.

Himmler ordered Blome to study various dissemination methods of plague bacteria for offensive warfare. According to Blome, he shared with Himmler his fears regarding the dangerous boomerang effect a plague bomb would most likely have on Germany. Himmler told Blome that in that case, he should get to work immediately to produce a vaccine to prevent such a thing. To expedite vaccine research, Blome said, Himmler ordered him “to use human beings.”

He, Blome, was in charge of creating the biological weapons; Dr. Schreiber was in charge of protecting Germans against biological weapons, should they be used—Major General Dr. Schreiber specialized in epidemic control. The sword and the shield.

During the war, Dr. Kliewe told Blome that it was the Russians who had the single most extensive biological weapons program in the world—a program more advanced even than that of the Japanese. Further, the Russians had managed to capture everything from Dr. Traub’s laboratory on Riems, including Dr. Traub’s Turkish strain of cattle plague. Then, in the winter of 1945, the Russians had captured Blome’s bacteriological institute at Nesselstedt, outside Posen. This meant the Russians now had the Reich’s most advanced biological weapons research and development facility, its steam chambers, incubators, refrigerators, and deep-freeze apparatus. They also had all of the pathogens—viral and bacterial—that Blome had been working with when he had fled west.

thirty-three of the fifty-two Ashcan internees were going to a new prisoner of war interrogation facility, this one located in the small town of Oberursel in the Taunus Mountains. Only later would Dolibois learn that many of these Nazis would be hired by the U.S. Army to write intelligence reports on work they had done during the war.

Ernst Kaltenbrunner was considered the most dangerous Nazi among the high command. At 6'4", he was a giant man with a massive frame, a pockmarked face, and a huge head with seven or eight deep dueling scars running across both sides of his forehead, cheeks, and chin. He drank and smoked heavily and was missing teeth. Kaltenbrunner was described by the British journalist Rebecca West as looking like “a particularly vicious horse.” He held a doctorate in law and specialized in secret police work. He was the head of the Reich Security Main Office and chief of the security police and the security services. He was as actively involved in concentration camp crimes as any Nazi had been. According to the OSS, even Heinrich Himmler was frightened of him.

July 6, 1945, in a classified memorandum with the subject heading “Exploitation of German Specialists in Science and Technology in the United States,” the Joint Chiefs of Staff finally approved—on paper—a Nazi scientist program. President Truman was not made aware of the initiative.

Participants, it was noted, should be hereafter referred to as “eminent German specialists” as opposed to “German scientists,” because not all the Nazis being requested for program approval had degrees in science. Included in the mix were Nazi bureaucrats, businessmen, accountants, and lawyers. The project also now had an official code name, Operation Overcast. The name Paperclip would not be used for another eight months.

A list of desired German scientists—“List I”—accompanied the memo. It included 115 rocket specialists.

Accompanying von Braun, Rees, and the five other V-2 engineers were four scientists from the Hermann Göring Research Institute, handpicked by Colonel Putt and headed for Wright Field. They were Theodor Zobel, Rudolph Edse, Wolfgang Noggerath and Gerhard Braun. Luftwaffe test pilot Karl Baur was also with the group; he had served as aircraft manufacturer Messerschmitt’s chief Me-262 test pilot. Accompanying him he had his mechanic, Andreas Sebald.

Fort Strong, on an island in the middle of Boston Harbor, had been used as a training camp during the Civil War and remained in use on and off through World War I. The fortresslike nature of the coastal defense facility made it an ideal place for a secret military program like Operation Overcast.

the army barracks was easily converted into what would become known as the Operation Overcast hotel. German prisoners of war were moved onto the island to work as staff, including as translators, cooks, bakers, and tailors. Kolm’s job was to process the scientists, which included fingerprinting, medical examinations, and coordination with the FBI. This all took time, and the Germans were not known for patience. Before long an insidious unease settled in among the scientists, Kolm recalled.

To pass the time the scientists stayed indoors and played Monopoly, which they called the “capitalists’ game.”

Hamill took six of them—Eberhard Rees, Erich Neubert, Theodor Poppel, August Schulze, Wilhelm Jungert, and Walter Schwidetzky—to Aberdeen Proving Ground, where they began translating, cataloguing, and evaluating the information from the Dörnten mine stash. Hamill’s next mission was to escort Wernher von Braun by train to Fort Bliss, Texas.

Any suggestion that Otto Ambros would one day have a prominent and prosperous place in civilized society, and that the American government would be just one of the governments to employ him, would have seemed pure fantasy. Then again, the Cold War was coming.

“The past is a foreign country.” —L. P. Hartley

summer of 1945, the Nazi scientist program underwent a significant organizational change. At the behest of the State-War-Navy Coordinating Committee, control over the program was removed from the Military Intelligence Division of the War Department, G-2, and given over to the Joint Chiefs of Staff. The newly created Joint Intelligence Objectives Agency (JIOA) would now be in charge of decision making for the rapidly expanding classified program. The JIOA was a subcommittee of the Joint Intelligence Committee, which provided national security information to the Joint Chiefs of Staff.

national security historian Larry A. Valero, who has written a monograph on the subject for the CIA, the JIC was and remains one of the most enigmatic of all the American intelligence agencies. “The JIC structure was always in motion, always morphing and changing, a flexible, ad-hoc system,” Valero says. “Subcommittees came and went, so did staff officers, but JIC decisions always had to be by consensus and were always reported to the Joint Chiefs.” Little has been written about the inner workings of the JIOA,

“The most important JIC estimates involved the military capabilities and future intentions of the USSR,” says Valero. Those intelligence estimates determined that the Soviets were ideologically hostile to the West and would continue to seek global domination, an attitude they had managed to skillfully conceal during the war. In September 1945, the JIC advised the Joint Chiefs that the Soviet Union would postpone “open conflict” with the West in the immediate future but only so it could rebuild its military arsenal and by 1952 be back at fighting strength. After this date, said the JIC, the Soviets would be ready and able to engage the United States in “total war.”

(the fourth report in the JIC 250 series) warned the Joint Chiefs that “eight out of ten leading German scientists in the field of guided missiles” had recently gone missing from Germany, had most likely been captured by the Soviets, and were now at work in the USSR. Similarly threatening, noted the report, two German physics institutes had been seized by the Red Army and reassembled in the USSR—not just the laboratories and the libraries but the scientists as well.

The employment of German scientists was specifically and strategically aimed at achieving military supremacy over the Soviet Union before the Soviet Union was able to dominate the United States.

The phrase “no known or alleged war criminal” could not remain as part of policy nomenclature for long, nor could the phrase “no ardent Nazis.”

The original scientists at Wright Field were listed as Dr. Gerhard Braun, motor research; Dr. Theodor Zobel, aerodynamics; and Dr. Rudolph Edse, rocket fuels; the specialists were Mr. Otto Bock, supersonics; Mr. Hans Rister, aerodynamics; and Mr. Albert Patin, a businessman. Their salaries averaged $12,480 a year, plus a $6.00 per diem—the equivalent of about $175,000 in 2013.

Nuremberg as a city had played a unique role in the rise of the Nazi Party. It had been the site of Hitler’s Nazi Party rallies—colossal military parades supported by as many as 400,000 Nazi loyalists—and home to the Nuremberg race laws.

Kept secret from the public was an astonishing hypocrisy. Less than 150 miles from the Nuremberg courtroom, several of the physicians who had participated in, and many others who were accessory to, these criminal medical experiments were now being employed by the U.S. Army at the Army Air Forces Aero Medical Center, the classified research facility in Heidelberg.

Von Greim was a legend. Renowned for his fearlessness in battle, in World War I he had recorded twenty-eight kills. In the 1920s and 1930s he was considered one of the top pilots in Germany