Editing Theodore Hall (section)

==Manhattan Project==
[[File:Los Alamos aerial view.jpeg|thumb|left|Modern-day [[Los Alamos National Laboratory|Los Alamos]] aerial view]]
[[File:Implosion Nuclear weapon.svg|thumb|right|Basic design of an [[Nuclear weapon design#Implosion-type weapon|implosion-type]] atomic bomb]]

At the age of 18, on the recommendation of [[John Hasbrouck Van Vleck|Prof. John Van Vleck]], Hall was hired as the youngest physicist to be recruited to work on the [[Manhattan Project]] at [[Los Alamos National Laboratory|Los Alamos]].<ref name=Goodrow /><ref name=nytobit/> At Los Alamos, after first helping to determine the critical mass of uranium used for "[[Little Boy]]",<ref name=Albright>{{cite book|last=Albright|first=Joseph|title=Bombshell: The Secret Story of America's Unknown Atomic Spy Conspiracy|year=1997|publisher=Times Book|location=New York|isbn=081292861X|author2=Marcia Kunstel|url-access=registration|url=https://archive.org/details/bombshellsecrets00albr}}</ref> Hall was assigned to conduct experiments on and tests of the implosion system ("Fat Man"). He was eventually, while still a teen, put in charge of a team working on that difficult task.

Hall later claimed that as it became clear in the summer of 1944 that Germany was losing the war and would not ever manage to develop an atomic bomb, he became concerned about the consequences of an American monopoly on atomic weapons once the war ended. He was especially worried about the possibility of the emergence of a fascist government in the United States, should it have such a nuclear monopoly and want to keep it that way.<ref>{{Cite web|url=http://spartacus-educational.com/Theodore_Hall.htm|title = Theodore Hall (Ted Hall)}}</ref> He was not alone. It was widely known inside the confines of Los Alamos, that [[Lieutenant general (United States)|Lieutenant General]] [[Leslie Groves]], director of the Manhattan Project, had revealed to a group of top physicists there at a dinner that the real target of the US atom bomb was the [[Soviet Union]],<ref name="Leaving the bomb project, Bulletin of the Atomic Scientists">{{cite journal |last1=Rotblat |first1=Joseph |title=Leaving the bomb project |journal=Bulletin of the Atomic Scientists |date=August 1985 |volume=41 |issue=40th Anniversary Issue |page=18 |doi=10.1080/00963402.1985.11455991 |bibcode=1985BuAtS..41g..16R |url=https://books.google.com/books?id=uwYAAAAAMBAJ&pg=PA18 |access-date=10 August 2023}}</ref> a shocking statement that led one top physicist, [[Josef Rotblat]], to resign from the Project, and others like [[Niels Bohr]] and [[Leo Szilard]] to vainly petition first Roosevelt, and later Truman to halt it, not use it on people in Japan, or to inform the Soviets about it.

On the pretext of returning to his home in New York City for his 19th birthday in October 1944, Ted Hall visited the headquarters of [[Amtorg Trading Corporation|Amtorg]], the Soviet Union trading company located in a loft building on 24th Street in Midtown Manhattan. There an American worker for Amtorg gave him the name and address of [[Sergey Nikolaevich Kurnakov|Sergey Kurnakov]], a military writer for ''Soviet Russia Today'' and ''Russky Golos''—the same contact that was also recommended to his Harvard friend, roommate and eventually initial spy courier [[Saville Sax]], by the head of a Soviet Cultural center in New York, Artkino. Unaware initially that Kurnakov was an [[NKVD]] agent, Hall handed him a report on the scientists who worked at Los Alamos, the conditions at Los Alamos, and the basic science behind the bomb.<ref name=Haynes>{{cite book|last=Haynes|first=John Earl|title=Spies: The Rise and Fall of the KGB in America|url=https://archive.org/details/spiesrisefallofk00john|url-access=registration|year=2009|publisher=Yale University Press|location=New Haven, CT|isbn=978-0300164381|pages=[https://archive.org/details/spiesrisefallofk00john/page/110 110–117]|author2=Harvey Klehr |author3=Alexander Vassiliev }}</ref> Saville Sax subsequently delivered the same report to the Soviet Consulate, which he visited under the guise of inquiring about relatives still in the Soviet Union. The two eventually met with [[Anatoli Yatskov|Anatoly Yatskov]], the New York station chief operating under the cover of being a Consular clerk, who two weeks later transmitted the information about both young men to NKVD headquarters in Moscow using a [[one-time pad]] [[cipher]].<ref name=Haynes /> After officially becoming an informant for the Soviet Union, Hall was given the code-name MLAD, a [[Slavic languages|Slavic]] root meaning "young", and Sax, who was almost a year older than Hall, was given the code-name STAR, a Slavic root meaning "old".{{Citation needed|date=August 2022}}

Kurnakov reported in November 1944:
{{blockquote|Rather tall, slender, brown-haired, pale and a bit pimply-faced, dressed carelessly, boots appear not cleaned for a long time, slipped socks. His hair is parted and often falls on his forehead. His English is highly cultured and rich. He answers quickly and very fluently, especially to scientific questions. Eyes are set closely together; evidently, [[Neurasthenia|neurasthenic]]. Perhaps because of premature mental development, he is witty and somewhat sarcastic but without a shadow of undue familiarity and cynicism. His main trait&nbsp;— a highly sensitive brain and quick responsiveness. In conversation, he is sharp and flexible as a sword&nbsp;... He comes from a Jewish family, though doesn't look like a Jew. His father is a furrier; his mother is dead&nbsp;... He is not in the army because, until now, young physicists in government jobs at a military installation were not being drafted. Now, he is to be drafted but has no doubts that he will be kept at the same place, only dressed in a military uniform and with a correspondingly lower salary.<ref>Sergei Kurnakov, report to NKVD headquarters (November, 1944)</ref>}}

{{multiple image
| width = 150
| footer = Espionage information procured by [[Klaus Fuchs]] and Theodore Hall, and to a lesser extent by [[David Greenglass]], led to the first Soviet device, "[[RDS-1]]", closely resembling Fat Man, even in its external shape.
| image1 = A-bomb (RDS-1).jpg
| alt1 = RDS-1
| caption1 = RDS-1
| image2 = Fat Man (replica of nuclear bomb).jpg
| alt2 = "Fat Man"
| caption2 = "Fat Man"
}}

Unbeknownst to Hall, [[Klaus Fuchs]], a Los Alamos colleague, and others still unidentified, were also spying for the Soviet Union; none seems to have known of the others. Sax acted as Hall's [[courier]] until spring of 1945 when, because he was returning to full-time student status at Harvard, he was replaced by [[Lona Cohen]].<ref name=Sulick /><ref name=McKnight>{{cite book|last=McKnight|first=David|title=Espionage and the Roots of the Cold war: The Constitutional Heritage|year=2002|publisher=Frank Cass Publishers|location=London|isbn=0-7146-5163-X|page=177}}</ref> [[Igor Kurchatov]], a scientist and the head of the [[Soviet atomic bomb project|Soviet atomic bomb effort]], probably used information provided by Klaus Fuchs to confirm corresponding information provided earlier by Hall. Despite other scientists giving information to the Soviet Union, Hall was the only known scientist to give details on the design of an atomic bomb until recent revelations{{when|date=December 2021}} of the role of [[Oscar Seborer]].<ref name=Albright />