Final answer:
The controversies involving Alger Hiss and Julius and Ethel Rosenberg reflected the post-World War II concern over spying by communists in the United States. The Hiss case involved accusations of espionage by a former State Department official, while the Rosenberg case involved the transfer of atomic secrets to the Soviet Union. Both cases became highly controversial and symbolized the fears and tensions of the Cold War era.
Step-by-step explanation:
The controversies involving Alger Hiss and Julius and Ethel Rosenberg reflected the post-World War II concern over spying by communists in the United States. After World War II, the fear of communism and the spread of Soviet influence led to a period known as the Red Scare. The Hiss case involved accusations of espionage by a former State Department official, while the Rosenberg case involved the transfer of atomic secrets to the Soviet Union. Both cases became highly controversial and symbolized the fears and tensions of the Cold War era.