Ethel and Julius Rosenburg were communists convicted of conspiracy. The Jewish couple from New York was accused of passing highly secretive documents during WWII about the atomic bomb to the Soviet Union. While Julius may have helped the soviets in developing the atomic bomb. There was virtually no evidence to to convict him, but they were convicted in 1951 and executed in 1953.
History may have been different had this case not happened. This case set fear in the minds of people that there really was a threat of an organization of spies in America. Fear led to political repression of left-wing speech or thought. While I don’t think fear of communist spies is something most people are concerned all that much about today, I do believe that this case has contributed to peoples’ general negative disposition towards communism or socialism and has made people more cautious about things they say. I don’t believe my life would be any different, I don’t really fear expressing my opinions if they are unpopular nor do I really fear communist spies.