---
title: "J. Robert Oppenheimer"
chunk: 12/17
source: "https://en.wikipedia.org/wiki/J._Robert_Oppenheimer"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:07:13.473219+00:00"
instance: "kb-cron"
---

The FBI under J. Edgar Hoover had been following Oppenheimer since before the war, when he showed Communist sympathies as a professor at Berkeley and had been close to members of the Communist Party, including his wife and brother. They strongly suspected that he himself was a member of the party, based on wiretaps in which party members referred to him or appeared to refer to him as a communist, as well as reports from informers within the party. He had been under close surveillance since the early 1940s, his home and office bugged, his phone tapped and his mail opened.
In August 1943, Oppenheimer told Manhattan Project security agents that George Eltenton, whom he did not know, had solicited three men at Los Alamos for nuclear secrets on behalf of the Soviet Union. When pressed on the issue in later interviews, Oppenheimer admitted that the only person who had approached him was his friend Haakon Chevalier, a Berkeley professor of French literature, who had mentioned the matter privately at a dinner at Oppenheimer's house.
The FBI furnished Oppenheimer's political enemies with evidence that intimated communist ties. These enemies included Strauss, an AEC commissioner who had long harbored resentment against Oppenheimer both for his activity in opposing the hydrogen bomb and for his humiliation of Strauss before Congress some years earlier. Strauss had expressed opposition to exporting radioactive isotopes to other nations, and Oppenheimer had called them "less important than electronic devices but more important than, let us say, vitamins."
On June 7, 1949, Oppenheimer testified before the House Un-American Activities Committee that he had associations with the Communist Party USA in the 1930s. He testified that some of his students, including David Bohm, Giovanni Rossi Lomanitz, Philip Morrison, Bernard Peters, and Joseph Weinberg had been communists at the time they had worked with him at Berkeley. Frank Oppenheimer and his wife Jackie testified before HUAC that they had been members of the Communist Party USA. Frank was subsequently fired from his University of Minnesota position. Unable to find work in physics for many years, he became a cattle rancher in Colorado. He later taught high school physics and was the founder of the San Francisco Exploratorium.
The triggering event for the security hearing happened on November 7, 1953, when William Liscum Borden, who until earlier in the year had been the executive director of the United States Congress Joint Committee on Atomic Energy, sent Hoover a letter saying that "more probably than not J. Robert Oppenheimer is an agent of the Soviet Union." Eisenhower never exactly believed the allegations in the letter but felt compelled to move forward with an investigation, and on December 3, he ordered that a "blank wall" be placed between Oppenheimer and any government or military secrets.
On December 21, 1953, Strauss told Oppenheimer that his security clearance had been suspended, pending resolution of a series of charges outlined in a letter, and discussed his resigning by way of requesting termination of his consulting contract with the AEC. Oppenheimer chose not to resign and requested a hearing instead. The charges were outlined in a letter from Kenneth D. Nichols, general manager of the AEC. Nichols, who had thought highly of Oppenheimer's work on the earlier Long-Range Objectives Panel, said that "in spite of [Oppenheimer's] record he is loyal to the United States." He nonetheless drafted the letter, but later wrote that he was "not happy with the inclusion of a reference concerning Oppenheimer's opposition to the hydrogen bomb development."
The hearing that followed in April–May 1954, which was held in secret, focused on Oppenheimer's past communist ties and his association during the Manhattan Project with suspected disloyal or communist scientists. It then continued with an examination of Oppenheimer's opposition to the H-bomb and stances in subsequent projects and study groups. A transcript of the hearings was published in June 1954, with some redactions. In 2014, the U.S. Department of Energy made the full transcript public.

One of the key elements in this hearing was Oppenheimer's earliest testimony about George Eltenton's approach to various Los Alamos scientists, a story that Oppenheimer confessed he had fabricated to protect his friend Haakon Chevalier. Unknown to Oppenheimer, both versions were recorded during his interrogations of a decade before. He was surprised on the witness stand with transcripts of these, which he had not been given a chance to review. In fact, Oppenheimer had never told Chevalier that he had finally named him, and the testimony had cost Chevalier his job. Both Chevalier and Eltenton confirmed mentioning that they had a way to get information to the Soviets, Eltenton admitting he said this to Chevalier and Chevalier admitting he mentioned it to Oppenheimer, but both put the matter in terms of gossip and denied any thought or suggestion of treason or thoughts of espionage, either in planning or in deed. Neither was ever convicted of any crime.
Teller testified that he considered Oppenheimer loyal to the U.S. government, but that: