Question

what was the cause of the
ed scare\ of the 1920s? spanish flu epidemic julius & ethel rosenberg the russian revolution of 1917 charles lindberg

Explanation:

The "Red Scare" of the 1920s was a period of intense fear and suspicion of communism and radical political ideas in the United States. The Russian Revolution of 1917, which led to the establishment of the world's first communist state, the Soviet Union, was a major cause of this fear. Americans were worried that similar revolutionary ideas might spread to the United States and threaten the existing social and political order.

Answer:

the Russian Revolution of 1917