The Operation Paperclip: When Nazi Scientists Were Brought To America

In the summer of 1945, the United States made a decision it would spend the next seventy years trying not to admit it had made. It opened its borders, quietly and selectively, to roughly 1,600 Nazi scientists, engineers, and technicians — many of them card-carrying members of the SS, several of them implicated directly in concentration-camp medical experimentation — and put them to work at the highest levels of American defense, intelligence, and aerospace.

The operation was called Project Paperclip. It is sometimes referred to as Operation Overcast in its earliest phase. It ran in various forms from 1945 until at least 1959 — and the people brought in under it stayed embedded inside American institutions for decades after that.

Most American children learn that Wernher von Braun built the Saturn V rocket that carried Apollo 11 to the Moon. Far fewer learn that von Braun was a major in the Waffen-SS who had personally toured the Mittelwerk underground factory where his V-2 rockets were assembled by concentration-camp slave labor under conditions that killed an estimated 20,000 prisoners. Both facts are documented in the declassified record. They are simply never placed in the same sentence — until you start looking for them yourself.

How Operation Paperclip Started

The operation began as a tactical response to a strategic problem. As Allied forces advanced through Germany in the spring of 1945, the US military realized that Nazi scientific assets — rocket programs, jet aircraft, biological and chemical weapons research, advanced metallurgy, ballistic missile guidance — were about to fall into Soviet hands. The Cold War had not officially begun. The race for German scientific personnel already had.

The first wave of recruitment was called Operation Overcast. Its scope was modest — pull a few hundred specialists into temporary US custody for debriefing. By the autumn of 1945 the scope had ballooned. Whoever the Americans could grab before the Soviets grabbed them, the Americans would grab. Crimes against humanity, slave labor, concentration-camp experimentation — none of it was treated as a disqualifier.

The operation got its working name, “Paperclip,” from a literal office practice. When a recruited German scientist’s file contained politically problematic material — Nazi Party membership, SS rank, documented involvement in war crimes — a paperclip was attached to the cover. The paperclip indicated that the file would need to be “sanitized” before the scientist could be cleared for US entry. The euphemism was internal. The intent was unambiguous.

Truman’s Ban — And How It Was Bypassed

President Harry Truman authorized the project in September 1946. His authorization came with an explicit restriction: no scientist with significant Nazi Party involvement or documented war-crime activity was to be admitted to the United States.

This created an immediate operational problem. Most of the scientists the US most wanted to recruit were exactly the scientists Truman had just banned.

The solution, executed by the Joint Intelligence Objectives Agency (JIOA), was to rewrite the files. According to documents declassified in 2014 and analyzed by investigative journalist Annie Jacobsen, the JIOA systematically altered the personnel records of high-value recruits to remove or downplay Nazi affiliations. Memos refer to this process as “expedient processing.” In plain English: evidence laundering, executed by a US government agency, on behalf of war criminals.

By the time the sanitized files reached the State Department for visa approval, the scientists’ pasts had been edited into the shape of cooperative civilians who had merely happened to live in Germany during the war. Truman’s order remained on paper. In practice, it was systematically ignored — with the full knowledge of the agencies charged with enforcing it.

The Scientists Who Got In

The Paperclip roster was long. The following are among the most consequential — and the most documented — recruits.

Wernher von Braun — NASA’s Chief Rocket Designer

Von Braun is the most famous Paperclip recruit. He was the technical director of the Nazi V-2 program — the rocket that killed roughly 9,000 civilians in London and Antwerp during the closing months of WWII. He held the SS rank of Sturmbannführer (major). He personally visited the Mittelwerk plant where his rockets were built by slave laborers from Mittelbau-Dora and Buchenwald.

The US Army recruited him in May 1945. By 1955 he was a US citizen. By 1960 he was director of the Marshall Space Flight Center in Huntsville, Alabama. The Saturn V rocket that carried Apollo 11 to the Moon was his design. He died in 1977 a celebrated American scientist. The slave-labor component of his career has been documented since the 1980s but remains absent from most popular biographies — a fact that researchers exploring the deeper layers of the Apollo program have repeatedly flagged.

Hubertus Strughold — “Father of Space Medicine”

Strughold ran the Luftwaffe’s Institute for Aviation Medicine during the war. His department conducted human experiments at Dachau and other concentration camps — exposing prisoners to extreme cold, low pressure, and seawater to study aviation survival limits. Some subjects died during the experiments. Some died afterward.

The US Air Force brought him to America in 1947. He became the chief scientist of the Aerospace Medical Division at Brooks Air Force Base. The Aeromedical Library at Brooks was named after him in 1977. The name was quietly removed in 2006, after sustained pressure from Holocaust survivors and historians — almost three full decades after Strughold himself had died.

Kurt Blome — Nazi Biological Warfare Chief

Blome ran Nazi Germany’s biological weapons program. He oversaw research at Posen on plague and other lethal agents, with human test subjects drawn from concentration camps. He was indicted at the Nuremberg Doctors’ Trial in 1947 and acquitted under contested circumstances that several historians have called outright suspicious.

Two months after his acquittal he was contracted by the US Army Chemical Corps to consult on biological weapons. The recruitment documents are now declassified. The phrase used in the contract is “expert consultation.”

Walter Schreiber — Typhus Experiments

Schreiber was the Surgeon General of the Wehrmacht. He approved typhus vaccine experiments on prisoners at Buchenwald and Natzweiler. He was held by the Soviets after the war, then transferred to American custody, then brought to the US in 1951 to work at the School of Aviation Medicine in Texas. After his Nazi past became public knowledge in 1952, he was quietly relocated to Argentina with US assistance — the same Argentine pipeline that other escaped Nazi war criminals had been using since 1945.

Reinhard Gehlen — Father of West German Intelligence

Gehlen ran Nazi military intelligence on the Eastern Front. When the war ended he turned over his Soviet-intelligence files to the Americans in exchange for protection. The CIA placed him in charge of an entire intelligence apparatus — the “Gehlen Organization” — that would later become the BND, the West German foreign intelligence service. The Gehlen network is now known to have been heavily infiltrated by former SS personnel. Some of them were simultaneously working for the KGB. The CIA knew this. The CIA kept paying.

Otto Ambros — IG Farben Chemist

Ambros was a chemist at IG Farben who oversaw the production of Zyklon B at Auschwitz and helped develop the nerve agents Sarin and Tabun. He was convicted at Nuremberg of slavery and mass murder. He served only a fraction of his sentence. After his release, he worked as a chemical industry consultant for the US Army Chemical Corps and several American Fortune-500 corporations until his death in 1990.

What They Built in America

The Paperclip recruits were not symbolic acquisitions. They worked. They built things that shaped the next fifty years of American power — and arguably, the fifty after that.

The American space program. The Saturn V, the Redstone rocket, the early ICBM designs, the foundational aerospace medicine research that made manned spaceflight possible — von Braun’s team and Strughold’s labs were core to all of it. Without Paperclip, the Apollo program almost certainly would have run several years behind schedule. It might not have beaten the Soviets to the Moon at all.

The Cold War intelligence apparatus. The CIA’s early East European operations leaned heavily on Gehlen’s network. The methods, the assets, and in many cases the actual personnel were directly inherited from Nazi military intelligence. This is the part of the story that the deeper history of American institutional power rarely acknowledges in popular accounts.

The biological and chemical weapons programs. Fort Detrick’s biowarfare research drew on consultations with Nazi-era specialists. The chemical weapons stockpile that defined US Cold War deterrence was built partly on Nazi-era German chemistry. The infamous MKUltra program that ran throughout the 1950s and 60s — testing LSD, hypnosis, electroshock and other coercive techniques on unwitting American civilians — overlapped significantly with the coercion-research knowledge brought over by Paperclip recruits. The full continuity is hard to prove on the public record only because so much of the record was deliberately destroyed.

The Cover-Up — How Their Pasts Were Erased

The systematic file-rewriting that allowed Paperclip recruits to enter the US is now a matter of public record. The JIOA’s own internal correspondence, declassified in tranches between 2003 and 2014, describes the process in unembarrassed bureaucratic language.

Recruits’ files were classified into “white” (no problematic Nazi history), “gray” (problematic but recoverable), and “black” (too compromised to whitewash). The black files were sometimes removed entirely. The gray files were edited until they became white. Memos from the period reference “the necessity of altering the record” with the same matter-of-factness as a budget memo. The American government did not merely shelter war criminals. It actively manufactured their innocence.

Once the recruits arrived in the United States, ongoing PR work continued for decades. Biographies were sanitized. Honors were awarded. Asteroids, awards, and buildings were named after people whose actual wartime conduct, if widely known, would have made every American institution involved look complicit. In many cases, the institutions were complicit. The recruits’ pasts had not been hidden from them. They had simply been deemed not relevant.

Modern Echoes — Where the Paperclip Network Still Lives

The formal program ended in 1959. The patterns it established did not.

The same agencies that ran Paperclip — JIOA’s institutional descendants, the CIA, the US Air Force — went on to run programmes that look, in declassified hindsight, like direct continuations of the same playbook. Project Stargate, the CIA’s two-decade remote-viewing programme that ran from the 1970s into the 1990s, drew on coercion-research methods with clear continuity to Nazi-era experimentation. The secret CIA research programmes that have been declassified in tranches over the past decade describe a research culture that, in its willingness to test invasive techniques on unwitting subjects, is recognisably descended from the institutional culture Paperclip recruits helped build.

And the modern frontier — brain-computer interfaces, deep-implant neural research, “private” biotech labs operating under defense contracts — is staffed by institutions that trace their organisational DNA back to Fort Detrick, to Brooks Air Force Base, to the Aerospace Medical Division. None of this requires a single living Paperclip recruit. The recruits’ real legacy was institutional. The institutions are still here.

What’s Confirmed vs What’s Still Disputed

Confirmed: Operation Paperclip recruited approximately 1,600 Nazi scientists into the United States between 1945 and 1959. The JIOA systematically altered personnel files to bypass Truman’s ban. Many recruits had documented SS membership and concentration-camp involvement. Major figures including von Braun, Strughold, Blome, Schreiber, Gehlen, and Ambros were Paperclip recruits or directly adjacent to the program. The Apollo program drew heavily on Paperclip personnel. The CIA’s East European operations grew out of the Gehlen network.

Plausibly connected but not fully documented: The MKUltra program’s debt to Nazi-era coercion research is widely believed but not exhaustively documented on the public record — largely because the bulk of the MKUltra files were ordered destroyed by CIA Director Richard Helms in 1973. The full membership list of Paperclip recruits has never been entirely declassified. The Reinhard Gehlen network’s deep penetration by Nazi war criminals into NATO-era West German intelligence is well-documented but its full scope remains classified in some files.

Conspiracy-adjacent but contested: Claims of an organized “Fourth Reich” continuity-of-government program involving Paperclip recruits as a permanent shadow government — sometimes called ODESSA-derived theories — are contested by mainstream historians. ODESSA itself, the Nazi escape network, demonstrably existed; the scope and persistence of its post-1950s operations remain open questions.

The Declassified Documents — What We Know Now

The most comprehensive public-record archive on Operation Paperclip is held by the National Archives in College Park, Maryland. The JIOA’s internal correspondence is searchable. The recruitment files of many individual scientists — including von Braun, Strughold, and Blome — are available in unredacted form.

Annie Jacobsen’s 2014 book Operation Paperclip: The Secret Intelligence Program that Brought Nazi Scientists to America remains the most thorough single-volume treatment. Christopher Simpson’s earlier Blowback: America’s Recruitment of Nazis and Its Effects on the Cold War covers the intelligence-side of the program in greater depth. Linda Hunt’s Secret Agenda from 1991 was the first major investigative work and is still cited.

Frequently Asked Questions

How many Nazi scientists came to America under Operation Paperclip?

Approximately 1,600 between 1945 and 1959 — and that is the official figure. The actual number is almost certainly higher, because several parallel recruitment streams were not catalogued under the Paperclip program name and because the full archive has never been declassified.

Was Wernher von Braun a Nazi?

Yes — and not as a paper formality. He was a member of the Nazi Party and held the rank of Sturmbannführer (major) in the SS. He personally visited the Mittelwerk slave-labor plant where his rockets were built. The extent of his hands-on complicity is debated by historians; his knowledge of the conditions is not.

Did Operation Paperclip violate President Truman’s orders?

Yes. Truman’s September 1946 directive explicitly banned the entry of scientists with significant Nazi affiliations. The Joint Intelligence Objectives Agency systematically rewrote personnel files to circumvent the ban. This is now confirmed by declassified internal JIOA correspondence. The President of the United States was, in effect, kept on the wrong side of his own intelligence agencies.

Were any Paperclip scientists prosecuted at Nuremberg?

Several were indicted. Kurt Blome was acquitted under contested circumstances and recruited two months later. Otto Ambros was convicted of mass murder and slavery, served a fraction of his sentence, and became a US Army Chemical Corps consultant. Most Paperclip recruits were never tried at all.

What programs did Operation Paperclip lead to?

Directly: the US space program (NASA), the US ballistic missile program, the early CIA East European intelligence apparatus, and significant portions of US chemical and biological weapons research. Indirectly: the Apollo Moon landings, the MKUltra mind-control research, Project Stargate, and the architecture of West German postwar intelligence. Many of those programs are still operationally active in successor form.

Is Operation Paperclip still active?

The formal program ended in 1959. The institutional culture it built — the willingness of US intelligence agencies to absorb personnel with extreme backgrounds in exchange for strategic capability — never ended. Researchers tracking modern defense contracting and intelligence partnerships argue that the Paperclip pattern simply changed its surface paperwork.

The Bigger Question

Operation Paperclip is the cleanest documented example of a pattern that recurs across every declassified American intelligence program: a covert operation authorized at the highest levels, carried out in ways that would not have been politically possible if visible, and quietly normalised into the institutional fabric long after its formal end.

The Saturn V rocket put twelve Americans on the Moon. Some of the people who designed it had attended Nazi Party meetings, worn SS uniforms, and walked the floors of slave-labor factories. Both things are true. The longer this story recedes from public memory, the easier it becomes for the institutions Paperclip built to keep doing the next version of the same thing — quietly, at the highest levels, on behalf of national security, in the name of strategic necessity.