Brien McMahon, U.S. Senator

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James O'Brien "Brien" McMahon

Birthdate: (48)
Birthplace: Norwich, CT, USA
Death: July 28, 1952 (48)
Washington, DC, USA
Immediate Family:

Son of William McMahon and Eugenie McMahon
Husband of Rosemart Brainerd Turner

Managed by: Private User
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About Brien McMahon, U.S. Senator

Brien McMahon, born James O'Brien McMahon (October 6, 1903 – July 28, 1952) was an American lawyer and politician who served in the United States Senate (as a Democrat from Connecticut) from 1945 to 1952. McMahon was a major figure in the establishment of the Atomic Energy Commission, through his authorship of the Atomic Energy Act of 1946 (the McMahon Act).

McMahon served as chairman of the Senate Special Committee on Atomic Energy, and the first chairman of the Joint Committee on Atomic Energy. McMahon was a key figure in the early years of atomic weapons development and an advocate for the civilian (rather than military) control of nuclear development in the USA. Also, in 1952, McMahon proposed an "army" of young Americans to act as "missionaries of democracy", which sowed the seeds for what later became the Peace Corps.

McMahon was born James O'Brien McMahon in 1903 in Norwalk, Connecticut. McMahon graduated Fordham University in 1924. and then Yale University Law School, New Haven, Connecticut in 1927. McMahon changed his name to Brien McMahon the same year as being admitted to the bar.

McMahon began a practice in Norwalk and later served as a judge in the city, appointed to the position by Connecticut Governor Wilbur L. Cross. However, McMahon quickly resigned to become special assistant to the Attorney General of the United States in 1933. Attorney General Homer Cummings was also from Connecticut. McMahon in 1935 was appointed as United States Assistant Attorney General overseeing the Department of Justice's Criminal Division. Among prominent cases McMahon was associated with in the Criminal Division were the prosecutions of "John Dillinger's lawyer, Louis Piquette (for harboring a criminal) and the trials of gangsters associated with 'Baby Face' Nelson. However, the case which elevated McMahon to national renown and laid the foundation for his political career, was the Harlan County Coal Miner's case ...[,] a landmark trial as the first effort to uphold the Wagner National Labor Relations Act, i.e., to enforce the right of labor to form unions. The case became most famous, however, not for the legal principles at stake, but for the violence and scandal that surrounded the trial. [And, d]espite [a] disappointing outcome of the case, ... McMahon ... received wide public recognition and a reputation as a courageous and honest upholder of justice, both of which would further his political ambitions," according to a biography accompanying the introduction to his papers, held by Georgetown University library.

In 1939, McMahon left government service and resumed his law practice. In February 1940 McMahon married Rosemary Turner, and they had a daughter, Patricia. McMahon mounted a successful campaign for a Connecticut United States Senate seat in 1944, defeating incumbent John A. Danaher, with internationalism (McMahon) v. isolationism (Danaher) a major point of debate.

In late 1945, McMahon managed to be appointed as the Chairman of the Senate Special Committee on Atomic Energy, which was exploring legislative alternatives to the War Department sponsored May-Johnson bill. McMahon had no special knowledge of matters relating to atomic energy, but saw the opportunity as a means to assert himself as a new Senator, especially as the May-Johnson view was coming under increased attack from scientists and eventually even lost support of the White House. McMahon's Special Committee held many hearings over the course of late 1945 and early 1946, providing a forum for major arguments about domestic postwar legislation for controlling atomic energy. On December 20, 1945, McMahon introduced into the Senate legislation for an alternative atomic energy bill, which was quickly known as the McMahon bill. This was initially a very liberal bill towards the control of scientific research, and was broadly supported by scientists. McMahon himself framed the controversy as a question of military versus civilian control of atomic energy, even though the War Department bill was primarily a civilian bill as well. In the spring of 1946, several major revisions were made to the McMahon bill in order to appease more conservative elements in the Senate. The resulting bill passed the Senate and the House without major modifications. On August 1, 1946, President Harry Truman signed the McMahon bill into law as the Atomic Energy Act of 1946.

On July 16, 1945, an atomic bomb was successfully detonated at Alamogordo, New Mexico after which Senator Brien McMahon of Connecticut called it "the most important thing in history since the birth of Jesus Christ."

As part of the Atomic Energy Act of 1946, a special Congressional committee, the Joint Committee on Atomic Energy, was created. McMahon would be its chairman in 1946, and again in 1949-1952. In this position he was notably an advocate of an expanded American nuclear arsenal, as well as a major advocate for the building of the hydrogen bomb.

In 1952, before being diagnosed with what would become his fatal cancer, McMahon launched a campaign for the presidency, with the "campaign slogan ... 'The Man is McMahon' and his main platform ... to insure world peace through fear of atomic weapons." From his sickbed, he sent a message to the Democratic state convention in Hartford, Connecticut saying that if elected President, he would tell the Atomic Energy Commission to manufacture thousands of hydrogen bombs.

McMahon was reelected to his seat in 1950 and served until his death in Washington, D.C. in 1952, aged 48. McMahon is buried in St. Mary’s Cemetery in Norwalk.

A commemorative stamp honoring Brien McMahon and his role in opening the way to peaceful uses of atomic energy was issued by the United States on July 28, 1962 at Norwalk, Connecticut. The stamp features a portrait of McMahon facing a rendition of an atomic symbol.

Brien McMahon High School, in Norwalk, is named after him. Brien McMahon Hall, a residence hall at the University of Connecticut in Storrs, also bears his name.

Footage of McMahon is included in the 1982 documentary The Atomic Cafe giving a speech urging a reasoned response to the acquisition of atomic weapons contrasting with the more McCarthyite speeches of Republican Senators Owen Brewster, Richard Nixon and Democratic Representative Lloyd Bentsen.

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Brien McMahon, U.S. Senator's Timeline

October 6, 1903
Norwich, CT, USA
July 28, 1952
Age 48
Washington, DC, USA