Editing Vannevar Bush (section)

==== Manhattan Project ====
Bush played a critical role in persuading the United States government to undertake a crash program to create an [[atomic bomb]].{{sfn|Goldberg|1992|p=451}} When the NDRC was formed, the Committee on Uranium was placed under it, reporting directly to Bush as the Uranium Committee. Bush reorganized the committee, strengthening its scientific component by adding Tuve, [[George B. Pegram]], [[Jesse Beams|Jesse W. Beams]], [[Ross Gunn]] and [[Harold Urey]].{{sfn|Hewlett|Anderson|1962|p=25}} When the OSRD was formed in June 1941, the Uranium Committee was again placed directly under Bush. For security reasons, its name was changed to the Section&nbsp;S-1.{{sfn|Hewlett|Anderson|1962|pp=40–41}}

[[File:Hanford Site Selection Team.jpg|thumb|left|Left to right: Vannevar Bush, James B. Conant, Major General Leslie Groves and Colonel Franklin Matthias at the [[Hanford Site]] in July 1945 |alt=Four men stand in front of a car. The two on the left are wearing suits, the two on the right wear army uniforms with garrison caps and ties tucked in.]]
Bush met with Roosevelt and Vice President [[Henry A. Wallace]] on October 9, 1941, to discuss the project. He briefed Roosevelt on [[Tube Alloys]], the British atomic bomb project and its [[Maud Committee]], which had concluded that an atomic bomb was feasible, and on the [[German nuclear energy project]], about which little was known. Roosevelt approved and expedited the atomic program. To control it, he created a Top Policy Group consisting of himself—although he never attended a meeting—Wallace, Bush, Conant, Stimson and the [[Chief of Staff of the United States Army|Chief of Staff of the Army]], [[General (United States)|General]] [[George Marshall]].{{sfn|Hewlett|Anderson|1962|pp=45–46}} On Bush's advice, Roosevelt chose the army to run the project rather than the navy, although the navy had shown far more interest in the field, and was already conducting research into atomic energy for powering ships. Bush's negative experiences with the Navy had convinced him that it would not listen to his advice, and could not handle large-scale construction projects.{{sfn|Zachary|1997|p=203}}{{sfn|Hewlett|Anderson|1962|pp=51, 71–72}}

In March 1942, Bush sent a report to Roosevelt outlining work by [[Robert Oppenheimer]] on the [[nuclear cross section]] of [[uranium-235]]. Oppenheimer's calculations, which Bush had [[George Kistiakowsky]] check, estimated that the [[critical mass]] of a sphere of [[Uranium-235]] was in the range of 2.5 to 5&nbsp;kilograms, with a destructive power of around 2,000&nbsp;tons of TNT. Moreover, it appeared that [[plutonium]] might be even more [[fissile]].{{sfn|Hewlett|Anderson|1962|p=61}} After conferring with Brigadier General [[Lucius D. Clay]] about the construction requirements, Bush drew up a submission for $85&nbsp;million in [[fiscal year]] 1943 for four pilot plants, which he forwarded to Roosevelt on June 17, 1942. With the Army on board, Bush moved to streamline oversight of the project by the OSRD, replacing the Section&nbsp;S-1 with a new S-1 Executive Committee.{{sfn|Hewlett|Anderson|1962|pp=72–75}}

A week later, on June 23, President Roosevelt sent this one-sentence memo back to Bush: ''"Do you have the money?"''
<ref name="Edmondson">{{cite news |last1=Edmondson |first1=Catie |title=A A Reporter's Journey Into How the U.S. Funded the Bomb |url=https://www.nytimes.com/2024/01/17/us/politics/atomic-bomb-secret-funding-congress.html |access-date=22 January 2024 |publisher=The New York Times Company |date=January 18, 2024}}</ref>

Bush soon became dissatisfied with the dilatory way the project was run, with its indecisiveness over the selection of sites for the pilot plants. He was particularly disturbed at the allocation of an AA-3 priority, which would delay completion of the pilot plants by three months. Bush complained about these problems to Bundy and [[United States Under Secretary of War|Under Secretary of War]] [[Robert P. Patterson]]. Major General [[Brehon B. Somervell]], the commander of the army's [[Services of Supply]], appointed Brigadier General [[Leslie R. Groves]] as project director in September. Within days of taking over, Groves approved the proposed site at [[Oak Ridge, Tennessee]], and obtained a AAA priority. At a meeting in Stimson's office on September 23 attended by Bundy, Bush, Conant, Groves, Marshall Somervell and Stimson, Bush put forward his proposal for steering the project by a small committee answerable to the Top Policy Group. The meeting agreed with Bush, and created a Military Policy Committee chaired by him, with Somervell's chief of staff, Brigadier General [[Wilhelm D. Styer]], representing the army, and Rear Admiral [[William R. Purnell]] representing the navy.{{sfn|Hewlett|Anderson|1962|pp=78–83}}

At the meeting with Roosevelt on October 9, 1941, Bush advocated cooperating with the United Kingdom, and he began corresponding with his British counterpart, Sir&nbsp;[[John Anderson, 1st Viscount Waverley|John Anderson]].{{sfn|Hewlett|Anderson|1962|pp=259–260}} But by October 1942, Conant and Bush agreed that a joint project would pose security risks and be more complicated to manage. Roosevelt approved a Military Policy Committee recommendation stating that information given to the British should be limited to technologies that they were actively working on and should not extend to post-war developments.{{sfn|Hewlett|Anderson|1962|pp=264–270}} In July 1943, on a visit to London to learn about British progress on antisubmarine technology,{{sfn|Zachary|1997|p=211}} Bush, Stimson, and Bundy met with Anderson, [[Lord Cherwell]], and [[Winston Churchill]] at [[10 Downing Street]]. At the meeting, Churchill forcefully pressed for a renewal of interchange, while Bush defended current policy. Only when he returned to Washington did he discover that Roosevelt had agreed with the British. The [[Quebec Agreement]] merged the two atomic bomb projects, creating the [[Combined Policy Committee]] with Stimson, Bush and Conant as United States representatives.{{sfn|Hewlett|Anderson|1962|pp=276–280}}

Bush appeared on the cover of ''Time'' magazine on April 3, 1944.<ref>{{cite news |url=http://www.time.com/time/covers/0,16641,19440403,00.html |archive-url=https://web.archive.org/web/20081214231645/http://www.time.com/time/covers/0,16641,19440403,00.html |url-status=dead |archive-date=December 14, 2008 |title=Dr.&nbsp;Vannevar Bush |magazine=Time |date=April 3, 1944 |volume=XLIII |issue=14}}</ref> He toured the [[Western Front (World War II)|Western Front]] in October 1944, and spoke to ordnance officers, but no senior commander would meet with him. He was able to meet with [[Samuel Goudsmit]] and other members of the [[Alsos Mission]], who assured him that there was no danger from the German project; he conveyed this assessment to Lieutenant General [[Bedell Smith]].{{sfn|Bush|1970|pp=114–116}} In May 1945, Bush became part of the [[Interim Committee]] formed to advise the new president, [[Harry S. Truman]], on nuclear weapons.{{sfn|Hewlett|Anderson|1962|pp=344–345}} It advised that the atomic bomb should be used against an industrial target in Japan as soon as possible and without warning.{{sfn|Hewlett|Anderson|1962|pp=360–361}} Bush was present at the [[Holloman Air Force Base|Alamogordo Bombing and Gunnery Range]] on July 16, 1945, for the [[Trinity (nuclear test)|Trinity nuclear test]], the first detonation of an atomic bomb.{{sfn|Hewlett|Anderson|1962|p=378}} Afterwards, he took his hat off to Oppenheimer in tribute.{{sfn|Zachary|1997|p=280}}

Before the end of the Second World War, Bush and Conant had foreseen and sought to avoid a possible [[nuclear arms race]]. Bush proposed international scientific openness and information sharing as a method of self-regulation for the scientific community, to prevent any one political group gaining a scientific advantage. Before nuclear research became public knowledge, Bush used the development of biological weapons as a model for the discussion of similar issues, an "opening wedge". He was less successful in promoting his ideas in peacetime with President Harry Truman, than he had been under wartime conditions with Roosevelt.<ref name="Distillations">{{cite journal |last1=Meyer |first1=Michal |title=The Rise and Fall of Vannevar Bush |url=https://www.sciencehistory.org/distillations/magazine/the-rise-and-fall-of-vannevar-bush |journal=Distillations |publisher= [[Science History Institute]] |date=2018|volume=4 |issue=2 |pages=6–7 |access-date=August 20, 2018 }}</ref><ref name="Wellerstein">{{cite web |last1=Wellerstein |first1=Alex |title=Biological Warfare: Vannevar Bush's "Entering Wedge" (1944) |url=http://blog.nuclearsecrecy.com/2012/07/25/biological-warfare-vannevar-bushs-entering-wedge/ |website=Restricted Data |access-date=August 21, 2018|date=July 25, 2012}}</ref>

In "[[As We May Think]]", an essay published by the ''[[Atlantic Monthly]]'' in July 1945, Bush wrote: "This has not been a scientist's war; it has been a war in which all have had a part. The scientists, burying their old professional competition in the demand of a common cause, have shared greatly and learned much. It has been exhilarating to work in effective partnership."<ref name="As We May Think">{{cite news |last=Bush |first=Vannevar |url=https://www.theatlantic.com/magazine/archive/1945/07/as-we-may-think/3881/ |access-date=April 20, 2012 |title=As We May Think |date=July 1945 |newspaper=The Atlantic Monthly}}</ref>