A series of highly publicized legal cases followed, which fueled the growing anticommunist hysteria. Whittaker Chambers, an editor at Time magazine, testified before HUAC that during the 1930s, Alger Hiss, a high-ranking State Department official, had given him secret government documents to pass to agents of the Soviet Union. Hiss vehemently denied the charge, but a jury convicted him of perjury and he served five years in prison. A young congressman from California and a member of HUAC, Richard Nixon achieved national prominence because of his dogged pursuit of Hiss. In another celebrated case, the Truman administration put the leaders of the Communist Party on trial for advocating the overthrow of the government. In 1951, eleven of them were sentenced to five years in prison.

The most sensational trial involved Julius and Ethel Rosenberg, a working-class Jewish communist couple from New York City (quite different from Hiss, a member of the eastern Protestant “establishment”). In 1951, a jury convicted the Rosenbergs of conspiracy to pass secrets concerning the atomic bomb to Soviet agents during World War II (when the Soviets were American allies). Their chief accuser was David Greenglass, Ethel Rosenberg’s brother, who had worked at the Los Alamos nuclear research center.

Demonstrators at a 1951 rally in Washington, D.C., demanding the execution of Julius and Ethel Rosenberg.

The case against Julius Rosenberg rested on highly secret documents that could not be revealed in court. (When they were released many years later, the scientific information they contained seemed too crude to justify the government’s charge that Julius had passed along the “secret of the atomic bomb,” although he may have helped the Soviets speed up their atomic program.) The government had almost no evidence against Ethel Rosenberg, and Greenglass later admitted that he had lied in some of his testimony about her. Indeed, prosecutors seem to have indicted her in the hope of pressuring Julius to confess and implicate others. But in the atmosphere of hysteria, their conviction was certain. Even though they had been convicted of conspiracy, a far weaker charge than spying or treason, Judge Irving Kaufman called their crime “worse than murder.” They had helped, he declared, to “cause” the Korean War. Despite an international outcry, the death sentence was carried out in 1953. Controversy still sun rounds the degree of guilt of both Hiss and the Rosenbergs, although almost no one today defends the Rosenbergs’ execution. But these trials powerfully reinforced the idea that an army of Soviet spies was at work in the United States.

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