Was Robert Oppenheimer a Communist? A Look at the Evidence

Was Robert Oppenheimer a communist? Was he actually a member of the Communist Party?

In American Prometheus, Kai Bird and Martin Sherwin examine the claims that scientist J. Robert Oppenheimer was a communist. They explain that his political activism and connections led to allegations of Communist Party membership.

Read more to learn what Bird and Sherwin learned and concluded.

Early Political Views and Activism

Was Robert Oppenheimer a communist? Bird and Sherwin investigate the roots of this claim. As Oppenheimer began his academic career, he became increasingly politically active—a development foreshadowed by his membership in the Student Liberal Club at Harvard in 1922. As Bird and Sherwin argue, Oppenheimer consistently supported progressive causes throughout the 1930s, a fact that contributed to accusations of Communist activities (accusations that haunted him later in life).

Bird and Sherwin note that, owing to economic turmoil following the Great Depression, dockworkers in Berkeley, California—Oppenheimer’s home at the time—started an 83-day strike that upended California’s economy. To show his support, Oppenheimer and his students attended left-wing rallies that celebrated the striking dockworkers. This development, Bird and Sherwin suggest, foreshadowed Oppenheimer’s later support for unions: He became an active member of the East Bay Teachers’ Union in the late 1930s, one of the few Berkeley academics to do so.

(Shortform note: Oppenheimer’s support for labor unions was shared by many progressives at the time. In the early 1930s, labor unions became a prominent liberal cause due to pro-union Democratic President Franklin Delano Roosevelt, who thought they could help revitalize the economy after the Great Depression. Moreover, the 1935 Wagner Act codified employees’ right to unionize, making issues of labor unions more salient to the American public.)

In addition to supporting workers’ rights, Oppenheimer became an active champion of the Spanish Republic—the democratically elected Republican Government that was under attack from fascist militants. According to Bird and Sherwin, Oppenheimer was documented as donating about $1,000 annually (around $20,000 in today’s money) in the late 1930s to the Spanish Republican cause. Crucially, Oppenheimer donated this money via Communist Party chapters in America because the Communist Party was directly assisting the Spanish Republic.

(Shortform note: In addition to donations from benefactors like Oppenheimer, the Spanish Republic attracted international support from some 35,000 foreign volunteers who fought against the fascists in the Spanish Civil War. But although President Roosevelt sought to convince Congress to aid the Spanish Republic, he was unsuccessful: In 1935, Congress passed the Neutrality Act that prohibited the US from providing weapons to Spain.)

Alleged Communist Party Membership

Because Oppenheimer worked closely with members of the Communist Party, many of his detractors alleged he was a Communist Party member himself. Against this allegation, Bird and Sherwin contend that, although Oppenheimer’s political views often aligned with Communist Party views, he was never a formal member.

In defense of this claim, Bird and Sherwin cite interviews with several Communist Party members that Oppenheimer had befriended—these friends reported that, although Oppenheimer often socialized with Communist Party members, he never paid dues to those in charge of Party finances, which members were required to do. Even more importantly, these friends claimed Oppenheimer was never subject to Party discipline, which would have required him to stop reading many of his favorite intellectuals, such as Freud and Hemingway.

Nonetheless, Bird and Sherwin acknowledge that certain Party members, like Oppenheimer’s friend and fellow Berkeley professor Haakon Chevalier, believed Oppenheimer was a Party member, citing his regular visits to Party meetings and his support of progressive political causes. Others pointed to Oppenheimer’s intimate relationships with Party members—Oppenheimer had a relationship with Jean Tatlock, a committed Party member, between 1936 and 1939, and his wife Kitty was a former Party member herself. But, Bird and Sherwin argue these friends were likely mistaken by Oppenheimer’s close proximity to the Party, which is distinct from Party membership.

The Development of the Communist Party USA During the 1930s

Allegations of Communist Party membership grew more common in the 1930s due to the growth of the Communist Party USA (CPUSA). During the Great Depression, which crippled the US economy and brought unemployment close to 25%, the CPUSA became increasingly popular as an alleged champion for the unemployed, with some 65,000 members throughout the 1930s. Experts even point out that the liberal left often worked alongside CPUSA members when their political aims overlapped in the ’30s.

However, the 1939 Nazi-Soviet Pact—an agreement between Nazi Germany and the Soviet Union not to invade one another—greatly damaged the CPUSA’s reputation, as it aligned the Soviets (who were led by the Communist Party) with America’s enemies. For this reason, the allegations of CPUSA membership leveled against Oppenheimer became much more harmful in the late ’30s and early ’40s, as indications of sympathy with the Communist Party were considered signs of disloyalty.

The 1954 Security Clearance Hearing

Though Oppenheimer had spearheaded the creation of the atomic bomb and served on various committees consulting the government on nuclear policy, he was often targeted by his political enemies after the atomic bomb for his past connections to communism. According to Bird and Sherwin, the animosity toward Oppenheimer culminated in December 1953, when he learned that the Atomic Energy Commission (AEC) intended to revoke his security clearance.

In May 1954, the panel voted two to one to revoke Oppenheimer’s security clearance, deeming Oppenheimer a security risk (though affirming his loyalty to the US). The next month, AEC commissioners ratified the decision in a four-to-one vote.

Was Robert Oppenheimer a Communist? A Look at the Evidence