Operation Paperclip: How the US Recruited Nazi Scientists After WWII

In the final months of World War II, American military and intelligence officers fanned out across defeated Germany with a mission that had nothing to do with occupation or denazification. They were hunting scientists: the engineers, physicists, and chemists who had built Hitler’s rockets, nerve agents, and aviation technology. The program that resulted, eventually codenamed Operation Paperclip, transferred more than 1,600 German specialists into American employment between 1945 and 1959, providing the United States with a decisive technological edge in the emerging Cold War while quietly burying the wartime records of men who had, in many cases, committed serious crimes.^[1] It remains one of the most consequential and morally contested covert programs in American history.

Origins: The Race to Capture German Technology

The strategic logic behind Paperclip was straightforward: Germany in 1945 possessed scientific and engineering capabilities that far exceeded those of any other nation in several critical fields. The V-2 ballistic missile, developed at the Peenemunde Army Research Center under the direction of Wernher von Braun, represented a generational leap beyond anything the Allies had produced.^[2] German aviation engineers had developed jet and rocket aircraft that outperformed Allied propeller-driven fighters. The Wehrmacht’s chemical weapons program had synthesized the nerve agents tabun and sarin, compounds unknown to Allied chemists. German submarine and radar technology, optical systems, and medical research all represented intellectual capital that the United States, the Soviet Union, and Britain all urgently wanted to acquire.

American efforts to capture this technology began before Germany’s formal surrender. Operation Alsos, a joint military and scientific mission launched in 1943, followed Allied forces into occupied Europe to seize atomic research materials and personnel before the Soviets could reach them.^[3] The Joint Intelligence Objectives Agency (JIOA), established in 1945 under the Joint Chiefs of Staff, was tasked with identifying, recruiting, and relocating German scientific talent to the United States. Its initial directive, issued in July 1945 and known as the Osenberg List operation, used a roster of German scientists compiled by Nazi official Werner Osenberg to identify priority targets for recruitment.

The program was initially called Operation Overcast before being renamed Paperclip in early 1946. The new name derived from the practice of JIOA officers attaching paperclips to the files of scientists they wished to recruit, distinguishing them from ordinary prisoners of war and denazification cases.^[1]

The Problem: Presidential Policy and Nazi Records

From the outset, Operation Paperclip operated in direct tension with official American policy. President Truman’s directive governing the program explicitly prohibited the immigration of “ardent Nazis” or individuals who had been “more than nominal participants” in the Nazi party.^[4] The State Department’s visa regulations similarly barred entry to individuals with records of war crimes or crimes against humanity.

The JIOA’s response to these constraints was systematic falsification. Agency officers reviewed the security dossiers and military records of targeted scientists, identified incriminating information relating to Nazi party membership, SS affiliation, war crimes allegations, and use of concentration camp slave labor, and then altered or omitted that information before forwarding files to the State Department and immigration authorities. The sanitized dossiers allowed scientists who would have been ineligible for immigration under existing law to enter the United States as government contractors.^[1]

The scale of this deception was substantial. Historian Annie Jacobsen, whose 2014 book Operation Paperclip: The Secret Intelligence Program That Brought Nazi Scientists to America drew on newly declassified JIOA files, documented case after case of scientists whose original security assessments described them as security risks or war criminals, only for those assessments to be replaced by cleared versions.^[5] The pattern was consistent enough to constitute institutional policy rather than individual misconduct.

Wernher von Braun and the V-2 Team

No figure in Operation Paperclip was more prominent or more controversial than Wernher von Braun. The director of the V-2 development program at Peenemunde, von Braun was a member of both the Nazi party (from 1937) and the SS (from 1940), holding the rank of Sturmbannfuhrer (major).^[6] The V-2 rockets he developed were produced at the Mittelwerk underground factory using forced labor drawn from the Dora concentration camp. Approximately 12,000 concentration camp prisoners died during V-2 production, a death toll that exceeded the number of people killed by the rockets themselves when deployed against London and Antwerp.

Von Braun surrendered to American forces in May 1945, along with some 125 members of the Peenemunde rocket team, who had moved westward specifically to surrender to Americans rather than Soviets. His original JIOA security report described him as a potential security threat and noted his SS membership. That report was replaced by a cleared version, and von Braun was transported to the United States in September 1945 as part of the first Paperclip cohort.^[1]

Von Braun went on to direct the development of the Redstone and Jupiter ballistic missiles for the US Army at the Redstone Arsenal in Huntsville, Alabama. He subsequently became the first director of NASA’s Marshall Space Flight Center and served as the chief architect of the Saturn V rocket that carried Apollo astronauts to the moon in 1969. His transformation from Nazi weapons developer to American space hero represents Paperclip’s most visible legacy: a career that embodied both the program’s technological achievements and its moral compromises.

Beyond Rockets: The Breadth of Paperclip Recruitment

The public narrative of Paperclip tends to focus on the rocket program, but the operation encompassed a far wider range of scientific disciplines. The US Army Chemical Corps recruited German chemists who had worked on nerve agent development, including specialists in tabun and sarin production. These recruits contributed to American chemical weapons programs at Edgewood Arsenal in Maryland, where research on chemical and biological warfare agents continued through the Cold War.^[1]

German aviation engineers and aerodynamicists were recruited to work at Wright-Patterson Air Force Base in Ohio and the Naval Air Material Center in Philadelphia, contributing to the development of early American jet aircraft and high-speed aeronautics. The United States Army Air Forces brought in Luftwaffe flight surgeons and aviation medicine specialists, some of whom had conducted experiments on concentration camp prisoners, to advise on pilot physiology, high-altitude flight, and ejection seat design.

The Navy recruited specialists in submarine technology, acoustic research, and mine warfare. The Signal Corps brought in German radar and electronics engineers. The medical community received German pharmacologists and physiologists. Across each of these domains, Paperclip scientists were integrated into American research institutions, defense contractors, and universities, contributing to the technological infrastructure of the postwar military-industrial complex.^[4]

The Soviet Parallel: Operation Osoaviakhim

The American program did not operate in a vacuum. The Soviet Union conducted its own parallel recruitment of German scientific talent, most dramatically through Operation Osoaviakhim, carried out on the night of October 22, 1946, when Soviet security forces simultaneously transported approximately 2,200 German specialists and their families to the USSR.^[7] Unlike Paperclip, which relied on voluntary (if coerced) cooperation, Osoaviakhim was a forced relocation: scientists were given hours’ notice, loaded onto trains, and transported to Soviet research facilities where they worked under close supervision for several years before most were repatriated to East Germany in the early 1950s.

The competitive dimension of German scientist recruitment was central to the JIOA’s justifications for Paperclip. Intelligence assessments consistently argued that any German specialist not brought to the United States would be available to the Soviets, and that allowing Soviet acquisition of key personnel would accelerate Moscow’s development of ballistic missiles, nuclear delivery systems, and chemical weapons. This framing transformed what might otherwise have been straightforwardly illegal into a Cold War necessity, a pattern of institutional reasoning examined in depth in the broader history of the CIA from OSS to modern day.

Walter Schreiber and the Limits of Tolerance

Not all Paperclip cases proceeded without friction. The case of Major General Walter Schreiber illustrates the limits of public and congressional tolerance for the program’s compromises. Schreiber, the former Surgeon General of the German Army, had been recruited by the JIOA to work at the School of Aviation Medicine at Randolph Air Force Base in Texas. In 1952, journalist Drew Pearson revealed that Schreiber had participated in human experimentation at concentration camps during the war, and that his Nuremberg testimony had implicated him in supervising medical experiments on prisoners.^[8]

The resulting public controversy forced the Air Force to acknowledge Schreiber’s presence and relocate him to Argentina, where he worked for the Argentine government. His case, and several similar episodes involving other Paperclip scientists, periodically forced the JIOA and its successor organizations to manage the political fallout of their recruitment decisions while continuing the underlying program.

The deeper problem that Schreiber’s case illustrated was structural: the JIOA’s record sanitization meant that the agencies employing Paperclip scientists often genuinely did not know the full extent of their recruits’ wartime activities. Declassified records have subsequently revealed that several Paperclip scientists who worked in American institutions for years had records that, if known at the time, would have made their employment legally and politically impossible.

Congressional and Public Accountability: The Long Delayed Reckoning

Operation Paperclip was not publicly disclosed until 1973, when journalist Clarence Lasby published a partial account based on declassified documents. More comprehensive disclosures followed through the 1980s and 1990s as Freedom of Information Act requests and congressional investigations opened additional records. The most significant congressional action came through the Nazi War Crimes Disclosure Act of 1998, which established the Nazi War Criminal Records Interagency Working Group (IWG) and mandated the declassification of records related to Nazi war criminals and their postwar activities.^[9]

The IWG’s work, completed in 2007, resulted in the declassification of approximately eight million pages of records from the CIA, FBI, Army, State Department, and other agencies. These records confirmed the systematic nature of the JIOA’s record falsification and revealed additional details about the wartime activities of specific Paperclip scientists. They also documented the CIA’s own postwar use of former Nazi intelligence officers, a parallel program centered on the Gehlen Organization, the West German intelligence network built from former Wehrmacht intelligence personnel under the direction of General Reinhard Gehlen, which eventually became the BND, explored in depth in our profile of Germany’s BND and Cold War espionage.

Technological Legacy: What Paperclip Produced

The technological contributions of Paperclip scientists to American capability were substantial and, in several cases, historically transformative. The rocket team under von Braun produced the Redstone missile, which became the basis for the first American intermediate-range ballistic missile; the Jupiter-C rocket, which launched America’s first satellite, Explorer 1, in January 1958; and ultimately the Saturn V, still the most powerful launch vehicle ever successfully flown.^[6]

German aerodynamicists contributed foundational research on swept-wing design and supersonic flight that informed the development of the F-86 Sabre and subsequent generations of American jet fighters. Chemical Corps recruits advanced American understanding of nerve agent pharmacology, contributing to both defensive countermeasures and, until the United States renounced offensive chemical weapons in 1969, to offensive stockpile development. Aviation medicine specialists produced research on pilot physiology and high-altitude survival that shaped cockpit design, pressure suit development, and ejection system engineering for decades.

The intelligence dimension of Paperclip extended beyond technology. The JIOA also recruited German intelligence officers and analysts who provided assessments of Soviet military capabilities, order of battle intelligence, and institutional knowledge of Soviet operational methods that American intelligence lacked in the immediate postwar period. This knowledge transfer contributed to early CIA and Defense Intelligence analytical capabilities during the critical years when the Soviet threat was being assessed and American Cold War strategy was being formulated.

The Moral Ledger: Historical Judgment and Ongoing Debate

Historians and ethicists continue to debate the moral calculus of Operation Paperclip. The case for the program rests on its strategic outcomes: the United States acquired technological capabilities that contributed to deterring Soviet aggression, winning the space race, and ultimately prevailing in the Cold War. The rocket program that sent humans to the moon would, its defenders argue, have developed far more slowly without the expertise the Peenemunde team brought.^[5]

The case against Paperclip operates on multiple levels. At the legal level, the program violated existing immigration law and presidential directives through systematic falsification of government records. At the moral level, it provided safe harbor, career advancement, and American citizenship to individuals who had committed or facilitated war crimes. At the institutional level, it established a precedent that national security imperatives could justify deception of the American public, Congress, and the law itself: a precedent whose echoes can be traced through subsequent episodes of covert action and institutional misconduct in American intelligence history, including many of the operations documented on this site.

The victims of the Mittelwerk and Dora camps, the concentration camp prisoners subjected to medical experiments, and the civilians killed by V-2 rockets have no representation in the technological achievements Paperclip produced. Their absence from the conventional Paperclip narrative reflects a broader pattern in how states construct the history of their intelligence and covert action programs: the outcomes are remembered; the costs borne by others are not.

Declassified Records: Where to Find Them

The primary archival sources for Operation Paperclip research are held at the National Archives and Records Administration (NARA) in College Park, Maryland. Record Group 330 (Records of the Office of the Secretary of Defense) and Record Group 319 (Records of the Army Staff) contain the core JIOA files, including original and sanitized security dossiers for individual scientists.^[4] The IWG’s declassification project produced a finding aid available through NARA’s online catalog.

The CIA’s own records relating to Paperclip-adjacent programs, including the Gehlen Organization and postwar use of former Nazi intelligence personnel, were released through the IWG process and are available through the National Security Archive at George Washington University. The FBI’s files on individual Paperclip scientists, obtained through FOIA requests by researchers including Jacobsen and historian Linda Hunt, document Bureau awareness of the scientists’ wartime records and, in several cases, active FBI resistance to their recruitment that was overridden by the JIOA and the Joint Chiefs.^[9]

Conclusion

Operation Paperclip encapsulates a tension that runs through the entire history of American intelligence and covert action: the conflict between strategic necessity and the rule of law, between pragmatic outcomes and moral accountability. It produced genuine technological achievements that shaped the modern world. It also involved systematic deception of American institutions, the laundering of war criminal records, and the conscious decision to prioritize Cold War advantage over the principles of justice that the Nuremberg trials had, in theory, established as universal. That tension was never resolved during the program’s operation; it has not been resolved in the decades of historical reckoning since. Operation Paperclip remains, in this sense, an unfinished chapter in the history of American intelligence.