1930s

The 1930s marked a double ascent for J. Robert Oppenheimer. At the University of California, Berkeley, he helped establish the most prominent center for theoretical physics in the United States; beyond the university, the Great Depression and the rise of fascism drew him into political work with friends on the left. The decade’s activism would later be recast as evidence against him, but in its own time it belonged to a wider effort to confront economic hardship and racial injustice.

Berkeley and the making of a scientific center

Oppenheimer entered the decade as a physicist shaped by his study of quantum physics in Germany, a new science he loved and actively promoted. At Berkeley, he became a senior professor and helped build a community in which theoretical physics could flourish. His scientific work and his public life developed alongside one another: he was not only an academic whose name appeared occasionally in local newspapers, but an increasingly prominent speaker on political questions and a signer of public petitions.

The political pressures surrounding him were local as well as international. San Francisco was fiercely polarized, and the longshoremen’s strikes had hardened divisions between left and right. Oppenheimer was alert to the possibility that political activity could damage the university’s reputation or his own position. In 1941, he told his colleague Ralph Fowler that he feared he might lose his job because the University of California was about to be investigated for radicalism. The apprehension shows how quickly visible activism could become a professional liability, even before the later federal scrutiny of his career.

Depression, fascism, and political engagement

The book presents Oppenheimer’s turn toward public causes as a response to events around him: the effects of the Great Depression at home and the advance of fascism abroad. He worked with friends, many of them communists or fellow travelers, in campaigns for economic and racial justice. These were not incidental contacts in an otherwise apolitical life. They formed part of what the biography calls some of his finest years, a period in which political engagement accompanied his work as a scientist and teacher.

Yet Oppenheimer’s activism did not amount to a fixed or uncomplicated political identity. The evidence describes him as politically vocal, but also responsive to events and at times cautious about consequences. A former graduate student recalled that he could draw back and become quiet when political pressure mounted, then become active again when something provoked him. This unevenness matters: his record is better understood as changing participation under changing circumstances than as a single, unaltered position.

The Nazi-Soviet pact and a changing political climate

The announcement on August 24, 1939, that the Soviet Union had signed a nonaggression pact with Nazi Germany unsettled left-wing intellectual circles. Germany and the Soviet Union invaded Poland a week later, beginning the war in Europe. Oppenheimer responded in a letter to physicist Charles Christian Lauritsen, relayed to his colleague Ralph Fowler, with skepticism toward premature certainty about the pact and its consequences. The episode placed his political judgment amid a crisis that confused and divided people who had previously shared causes.

His friend Haakon Chevalier defended the pact as a strategic necessity and joined hundreds of signatories to a public letter opposing the claim that the Soviet Union and totalitarian states were fundamentally alike. Oppenheimer’s name did not appear on that letter. Chevalier later recalled that Oppenheimer tried to explain the pact as a treaty of necessity, shaped in part by Western appeasement of Adolf Hitler at Munich, rather than simply as an alliance. That recollection is evidence of how Chevalier understood Oppenheimer’s reasoning, not proof that the two men held identical views or that Oppenheimer endorsed every Communist defense of Soviet policy.

The political argument continued into 1940. Oppenheimer was not a member of the League of American Writers, but he edited a pamphlet for a friend that argued against American entry into the European war. He may also have helped prepare two pamphlets called Reports to Our Colleagues, issued under the name of the College Faculties Committee of the Communist Party of California. Chevalier said Oppenheimer drafted them and paid for their printing and distribution; Gordon Griffiths corroborated his involvement in their production. The surviving evidence supports possible editing or drafting, but does not establish that Oppenheimer was their sole author or a member of the Communist Party.

Political record and later consequences

The pamphlets defended the New Deal’s domestic social programs and argued that the war was changing American political life. One portrayed the administration as abandoning liberal commitments while expanding armaments. Whether Oppenheimer had a hand in the more strident criticism of Franklin D. Roosevelt remains uncertain. The biography cautions that his known correspondence suggests disappointment with Roosevelt, not necessarily readiness to condemn him in the pamphlet’s terms. That distinction preserves the difference between documented involvement and an attribution that the evidence cannot settle.

In later years, Oppenheimer’s left-wing activity in Berkeley became part of the story told about his loyalty. During the postwar anticommunist campaign, investigators and political opponents joined his 1930s associations to his resistance to nuclear policies, especially the military’s plans for massive strategic bombing. The resulting portrayal collapsed political contact, past activism, and policy dissent into a single suspicion. In the 1954 security hearing, the charges again invoked his associations with Communists and his contributions to the Communist Party of California, despite earlier reviews of much of that history.

The decade therefore has a significance beyond its place in Oppenheimer’s personal chronology. It shows him building scientific institutions while taking part in a contested public culture, and it reveals how political activity that once seemed bound to urgent struggles for justice could later be used to narrow his authority as a public adviser. The biography treats those years not as a preordained path to his later ordeal, but as experiences whose meaning changed as the political climate changed.