ESPIONAGE AND THE
MANHATTAN PROJECT
(1940-1945)
Events: Bringing It All
Together, 1942-1945
Security was a way of life for the Manhattan Project. The goal was to
keep the entire atomic bomb program secret from Germany and
Japan. In this, Manhattan
Project security officials succeeded. They
also sought, however, to keep word of the
atomic bomb from reaching the Soviet Union. Although an ally
of Britain and the United States in the war against Germany, the Soviet Union
remained a repressive dictatorship and a potential future enemy. Here,
security officials were less successful. Soviet spies penetrated the
Manhattan Project at Los Alamos and several other locations, sending back to
Russia critical information that helped speed the development of the Soviet
bomb.
The
theoretical possibility of developing an atomic bomb was not a
secret. Fission
had been discovered in Berlin, and word of the breakthrough had spread
quickly around the world. The scientific basis for a sustained,
or even explosive, chain reaction was
now clear to any well-versed research physicist. Most physicists initially
may have thought an explosive chain reaction unlikely, but the possibility
could not be entirely discounted.
With an
atomic bomb program of its own, Germany attempted to build a large spy
network within the United States. Most German spies were quickly caught,
however, and none penetrated the veil of secrecy surrounding the Manhattan
Project. German physicists heard rumors and suspected an atomic
bomb project was underway in Britain, the United States, or both, but that was
all. Japan also had a modest atomic research
program. Rumors of the Manhattan Project reached Japan as well,
but, as with Germany, no Japanese spies penetrated the Manhattan
Project.
The
Soviet Union proved more adept at espionage, primarily because it was able
to play on the ideological sympathies of a significant number of Americans
and British as well as foreign émigrés. Soviet intelligence
services devoted a tremendous amount of resources into spying on the United
States and Britain. In the United States alone, hundreds of
Americans provided secret information to the Soviet Union, and the quality of Soviet sources in
Britain was even better. (In contrast, during the war neither the
American nor the British secret services had a single agent in Moscow.)
The Communist Party of the United States of America (CPUSA) had thousands of
members, a disproportionate number of whom were highly educated and likely to
work in sensitive wartime industries. Many physicists were members of the
CPUSA before the war. This does not mean that every member of the
CPUSA was willing to supply secret information to the Soviet Union, but some were and
some did.
Soviet intelligence first learned of
Anglo-American talk of an atomic bomb program in September 1941, almost a year
before the Manhattan Engineer District (MED) was
created. The information likely
came from John Cairncross, a member of the infamous "Cambridge Five" spies
in Britain.
(Cairncross served as a private secretary for a British government
official, Lord Hankey, who was privy to some British discussions of the MAUD
Report.) Another of the "Cambridge Five," Donald Maclean
(right),
also sent word of the potential for an atomic bomb to his Soviet handlers around
the same time. (Maclean was a key Soviet agent. In 1947 and 1948, he served
as a British liaison with the MED's successor, the Atomic
Energy Commission.) At the same time, the sudden
drop in fission-related publications emerging from Britain and the United States
caught the attention of Georgii Flerov, a young Soviet physicist, who in
April 1942 wrote directly to Josef Stalin to warn him
of the danger.
Soviet intelligence soon recognized the importance of the
subject and gave it the appropriate codename: ENORMOZ ("enormous").
Soviet intelligence headquarters in Moscow pressured their various
American residencies to develop sources within the Manhattan Project. Many of these early attempts at recruiting spies were
detected and foiled by the Federal Bureau of Investigation (FBI) and Manhattan
Project counterintelligence officials. In February 1943, they learned of Soviet attempts to contact physicists
conducting related work at the "Rad Lab" at the University
of California, Berkeley. The scientists in question were placed
under surveillance and, when possible, drafted into the military so that they
could be assigned away from sensitive subjects. Another scientist at the
Rad Lab caught passing information to the Soviet Union in 1944 was
immediately discharged. In early 1944, the FBI also learned of several "Met
Lab" employees suspected of divulging secret information to their Soviet
handlers. The employees were immediately dismissed. While these Soviet attempts at espionage were discovered and thwarted,
other Soviet spies went undetected.
Of the Soviet spies not caught during the war, one of the most valuable was the British physicist
Klaus
Fuchs. Fuchs first offered his services to Soviet intelligence in
late 1941. Soon thereafter, he began passing information regarding British atomic
research. Soviet intelligence lost contact with him in early 1944 but eventually found out
that Fuchs had been reassigned to the bomb
research and development laboratory at Los Alamos as part of the newly-arrived
contingent
of British scientists. Fuchs worked in the Theoretical Division at
Los Alamos, and from there he passed to his Soviet handlers detailed information regarding atomic weapons design.
Returning home to begin work on the British atomic program in 1946, he continued to pass secret information
to the Soviet Union
intermittently until he was finally caught (largely due to VENONA), and in January 1950 he confessed
everything.
For over
four decades, Klaus Fuchs was thought to be the only spy who was a
physicist at Los Alamos. In the mid-1990s, release of the VENONA
intercepts revealed an alleged second
scientist-spy: Theodore Hall. Like Fuchs, a long-time communist who
volunteered his services, Hall made contact with Soviet intelligence in November
1944 while at Los Alamos. Although not as detailed or voluminous as
that provided by Fuchs, the data supplied by Hall on implosion
and other aspects of atomic weapons design served as an important supplement and
confirmation of Fuchs's material. The FBI learned of Hall's espionage in
the early 1950s. Unlike Fuchs, however, under questioning Hall refused to
admit anything. The American government was unwilling to expose the VENONA
secret in open court. Hall's espionage activities had apparently ended by
then, so the matter was quietly dropped.
The most famous
"atomic spies," Julius and Ethel Rosenberg (right), never
worked for the Manhattan Project. Julius Rosenberg was an American engineer who by the
end of the war had been heavily involved in industrial espionage for years, both
as a source himself and as the "ringleader" of a network of
like-minded engineers dispersed throughout the country. Julius's wife, the
former Ethel Greenglass, was also a devoted communist, as was her brother
David. David Greenglass was an Army machinist, and in the summer of 1944 he was briefly assigned to
Oak
Ridge. After a few weeks, he was transferred to Los Alamos, where
he worked on implosion as a member of the Special
Engineering Detachment. Using his wife Ruth as the conduit,
Greenglass soon began funneling information regarding the atomic bomb to his
brother-in-law, Julius Rosenberg, who then turned it over to Soviet
intelligence. As Greenglass later explained, "I was young, stupid,
and immature, but I was a good Communist."
In March 1946, Greenglass left the Army. Soviet intelligence maintained
contact with him, urging him to enroll at the University of Chicago in order
to re-enter atomic research. The NKGB (the People's Commissary for State
Security and the predecessor to the KGB) offered to pay his tuition, but
Greenglass's application to Chicago was rejected. In 1950, the
confession of Klaus Fuchs led the FBI to his handler, Harry Gold, who in turn
led the FBI to David Greenglass. When confronted, Greenglass confessed, implicating his wife
Ruth and his brother-in-law, Julius
Rosenberg. This was soon confirmed through VENONA intercepts
(Rosenberg was codenamed ANTENNA and LIBERAL, Ethel was WASP, Greenglass was
BUMBLEBEE and CALIBER, and his wife Ruth was OSA). The "rolling
up" of the espionage ring stopped, however, with the Rosenbergs.
Julius and Ethel (who knew of her husband's activities and at times assisted
him) both maintained their innocence and refused to cooperate with authorities
in order to lessen their sentences. Because of his cooperation, Greenglass
received only 15 years, and his wife, Ruth, was never formally charged.
The Rosenbergs were sentenced to death. Authorities apparently hoped to use the
death sentences as leverage to get them to name names, but the Rosenbergs
maintained their silence. Despite a worldwide
campaign for clemency, Julius and Ethel Rosenberg were executed on June 19,
1953.
At least two other scientists associated with the Manhattan Project also
served as spies for Soviet Union: Allan Nunn May and Bruno Pontecorvo.
Another British physicist
who came over with James Chadwick in 1943,
May, unlike his colleague Klaus Fuchs, was not assigned to Los Alamos.
Instead, he was chosen to assist in the Canadian effort to construct a heavy
water-moderated reactor at Chalk
River, Ontario. During 1944, May visited the Met
Lab several times. Once during these visits, he even met Leslie
Groves. In February 1945, May passed what he had learned to Soviet
intelligence. His colleague at Chalk River, Bruno Pontecorvo, also served
as a spy. Pontecorvo was a former protégé of Enrico
Fermi. In 1936, Pontecorvo, who was Jewish, fled fascist Italy for
France. When France fell to the invading Nazi armies in 1940, Pontecorvo
was again forced to flee fascism. He was invited to join British atomic
research, and by 1943 he found himself assigned to the Chalk River facility.
Pontecorvo established contact with Soviet intelligence and began passing them
information about the atomic activities there. He continued his dual life
as a physicist and a spy in Canada until 1949 when he was promoted and moved
back to Britain to join the atomic research being conducted there.
Following the arrest of Klaus Fuchs, Pontecorvo's Soviet handlers became worried
that he would be exposed, and in 1950 Pontecorvo defected with his family to the
Soviet Union. Pontecorvo continued his work as a physicist in the Soviet
Union, eventually receiving two Orders of Lenin for his efforts, all the while
continuing to deny that he had been a spy during his years in Canada and
Britain.
A
number of spies within the Manhattan Project have never
been positively identified. Most are only known by their codenames, as
revealed in the VENONA decrypts. One source, an engineer or scientist who
was given the codename FOGEL (later changed to PERSEUS), apparently worked on
the fringes of the Manhattan Project for several years, passing along what
information he could. Soviet documents state that he was offered
employment at Los Alamos, but, to the regret of his handlers, he turned it down for
family reasons. Another source, a physicist codenamed MAR, first began
supplying information to the Soviet Union in 1943. In October of that year,
he was transferred to the Hanford Engineer Works.
In another case, a stranger one day in the summer of 1944
showed up unannounced
at the Soviet Consulate in New York, dropped off a package, and quickly
left. The package was later found to contain numerous secret documents relating
to the Manhattan Project. Soviet intelligence attempted to find out who
the deliverer of the package was so that they could recruit him. They never
could, however, determine his identity.
An Englishman codenamed ERIC also provided details of atomic research in 1943,
as did an American source codenamed QUANTUM, who provided secret information
relating to gaseous diffusion in the
summer of 1943. Who QUANTUM was or what became of him after the summer of
1943 remains a mystery.
Few aspects of the Manhattan Project remained secret from the
Soviet Union for long. Given the size of the pre-existing Soviet espionage network
within the United States and the number of Americans who were sympathetic to
communism or even members of the CPUSA themselves, it seems highly
unlikely in retrospect that penetrations of the Manhattan Project could have been
prevented. In most cases, the individuals who chose to provide information
to the Soviet Union did so for ideological reasons, not for money. They
were usually volunteers who approached Soviet intelligence themselves. Further, in most
cases, they were not aware that anyone else had chosen to do the
same thing. (Fuchs, Greenglass, and Hall were all at Los Alamos at the
same time, yet none of them knew of the espionage activities of the other
two.)
Soviet
espionage directed at the Manhattan Project probably
hastened by at least 12-18 months the Soviet acquisition of an atomic
bomb. When the Soviet Union conducted its first nuclear test on August 29,
1949 (right), the device they used was virtually identical in design to the one that had
been tested at Trinity four years
previously.
To view the next "event"
of the Manhattan Project, proceed to "1945: Dawn of
the Atomic Era."
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