What historical event caused a wave of paranoia in the U.S. leading to the "Red Scare"?

The "Red Scare" in the United States refers to the intense fear and paranoia surrounding the potential rise of communism and radical leftist movements, which was significantly heightened by the events of the Russian Revolution in 1917. This revolution led to the establishment of a communist government in Russia, which alarmed many in the U.S. who feared that similar ideologies could spread to their own country.

In the aftermath of the Russian Revolution, labor strikes and unrest became more prominent in the U.S., contributing to the belief that a communist uprising was imminent. The Bolshevik movement inspired a wave of suspicion against immigrants, labor unions, and anyone perceived as sympathetic to leftist ideologies. This culminated in a national campaign against communism, characterized by government actions, public fear, and social panic, all of which define the Red Scare.

Understanding this context helps to clarify how the Russian Revolution was a pivotal factor in triggering the Red Scare, while the other historical events listed did not directly relate to the emergence of communist fears in the United States.