During the late 1950s she served as reporter in Moscow for the North American Newspaper Alliance, and interviewed Lee Harvey Oswald as he was defecting to the Soviet Union in 1959.
[10] She was active in politics while at Brearley and thought that the nascent United Nations should have greater powers so as to be able to control nuclear weapons in the emerging Atomic Age.
[15] Following graduation in 1953, Johnson secured a brief position with the office of Senator John F. Kennedy of Massachusetts, where she worked on research regarding French Indochina.
[2][15] The recently married Kennedy indicated some amorous interest in her, but no affair between them took place;[16] in a 2013 interview with News.com.au, Johnson reflected that "I didn't love him.
"[15] Johnson saw Kennedy on a number of occasions over the next four years, including visiting him in the hospital following back surgeries that he underwent.
[2][6] These included topics such as the reaction in the Soviet literary magazine Novy Mir to the American Beat Generation writers.
"[8] In November 1959, at the Hotel Metropol Moscow, she met and interviewed the 20-year-old Lee Harvey Oswald, who was in the process of defecting to the USSR.
[2] Johnson became a visiting scholar at Harvard University's Russian Research Center,[2] a position she held from 1961 through the next some years.
[6] She was readmitted to the Soviet Union in 1962, this time working for The Reporter magazine, for which she wrote stories about intellectual life and Russian culture.
[8] In 1965, she was a significant contributor to, and co-editor of the academic volume Khrushchev and the Arts: The Politics of Soviet Culture, 1962–1964, which included some of the articles she had written while in the USSR.
[8][9] A review noted how the book traced a brief opening up of the arts during the Khrushchev Thaw before the premier himself directed a reversion to formulaic socialist realism.
[23] On November 22, 1963, Johnson was first shocked by the news of Kennedy's death, and then a second time by the identification of his killer, exclaiming to a friend: "My God, I know that boy!
[9] He was a freelance writer who covered the civil rights movement in the American South,[6] and wrote a history of the 1st Marine Division, The Old Breed.
[14][3][26] In 1967, McMillan translated the memoirs of Svetlana Alliluyeva, Stalin's daughter, who had gained much attention that year by defecting to the United States.
[8] She had first encountered Svetlana twelve years earlier, during her first visit to the Soviet Union, when under the name Stalina, she had taught a class at Moscow State University.
[2] However, it contained no conspiracy theories, only a very in-depth portrait of an unsuccessful, troubled, sometimes violent and ultimately small man, and sales of the book were modest.
[34] She also examined other people involved in the Oppenheimer matter,[32] including exploring differences of opinion among commissioners during the period in question.
[33] Foreign Affairs magazine said McMillan's work was "shorter and sharper" than the Bird–Sherwin one and "focuses more on the policy issues at the heart of the drama".
[16] Upon release, Publishers Weekly called it a "classic of the JFK assassination literature" and said that "McMillan's richly detailed, bleak, heartbreaking profile proves [Oswald]'s unfitness for any conspiracy outside his own head—and builds a compelling case for him as the demon-driven author of the Kennedy tragedy.
[36] She was a long-time resident of Cambridge, Massachusetts,[11] and her home there became a locus for intellectual conversations among friends, acquaintances, and family members along the lines of the European salon.