Seeds of Cold War Tension: The Manhattan Project

In a letter dated August 2, 1939, world famous physicist Albert Einstein alerted U.S. President Franklin D. Roosevelt about recent advances in nuclear physics, specifically concerning the possibility of a chain reaction in uranium, leading to the release of "vast amounts of power and large quantities of radium-like elements" in the very near future. This energy, he warned, could possibly be used to create new, very powerful bombs. He urged the president to secure "a supply of uranium ore" (as Germany appeared to be doing), and to "speed up the experimental work" on chain reactions already underway in the United States. One month later, on September 1, 1939, Germany invaded Poland. World War II had begun.
Roosevelt soon established the Advisory Committee on Uranium and the National Defense Research Committee to determine the feasibility of building one of these "powerful bombs". On January 19, 1942, just over a month after Japan attacked Pearl Harbor, President Roosevelt approved the construction of an atomic bomb. Within a few months, the Manhattan Engineer District was created, to be commanded by Colonel Leslie R. Groves. A pilot plant was built in Oak Ridge, Tennessee, and a scientific laboratory was built in Los Alamos, New Mexico. J. Robert Oppenheimer would be the laboratory director.
Oppenheimer personally visited universities across the country, seeking out and recruiting talented scientists to work on "Project Y", as it was code named. He appealed to their idealism, insinuating that this secret project could end the war, and maybe all wars. "Almost everyone new," he later wrote, "that this job, if it were achieved, would be part of history. This sense of excitement, of devotion and of patriotism in the end prevailed." Most of the scientists approached by Oppenheimer enthusiastically joined the project, bringing their own equipment and heading to New Mexico.
Once they arrived, the scientists worked at a feverish pace in unprecedented secrecy. Some scientists were given code names, they had to receive mail from a post office box instead of their address, and some homes and offices were wiretapped. Scientists were not allowed to discuss their work with their wives. The project itself was kept from congressional oversight, and was funded with a secret budget. Despite all of the extreme security measures, several scientists were later revealed as spies for the Soviet Union (we will discuss them in future installments).
In April of 1945, President Roosevelt passed away, and Harry S. Truman was sworn in as President. He was briefed a few weeks later on the Manhattan project and encouraged to keep it a secret (He later spilled the beans to Soviet leader Joseph Stalin at the Potsdam Conference in July of 1945). On May 7, 1945, Nazi Germany surrendered to the Allies, but the war with Japan continued to rage in the Pacific Theater.
On July 16, 1945, the Trinity Test was conducted in the Jornada del Muerto desert near Alamagordo, New Mexico. "Trinity" was the code name for the first nuclear bomb. After a short rain and lightening delay, the bomb was detonated at 05:29:21 MWT. Four hundred and twenty-five people were present at the test, and eyewitness accounts range from awestruck to terrified. Project worker and later assistant director Ralph Carlisle Smith described the explosion in wrenching detail:
"I was staring straight ahead with my open left eye covered by a welders glass and my right eye remaining open and uncovered.Suddenly, my right eye was blinded by a light which appeared instantaneously all about with no buildup of intensity. My left eye could see the ball of fire start up like a tremendous bubble or nob-like mushroom. It turned yellow, then red, and then beautiful purple. A hole was punched through the clouds but two fog rings appeared well above the white smoke column."
The world had entered the Atomic Age.

 *The above blog post was inspired by "The Manhattan Project: The Birth of Atomic Bomb in the Words of its Creators, Eyewitnesses, and Historians." Edited by Cynthia C. Kelly. 2007,2010. New York, Tess Press, Black Dog and Leventhal. All material is sourced from this collection, except for the quote from Ralph Carlisle Smith, which can be found on the website for the Atomic Heritage Foundation.