Define "paranoia." How was the paranoia of the 20s expressed? How was it related to isolationism?

Paranoia refers to a feeling that can exist in humans and which is heavily influenced by anxiety or by fear. People who suffer from this often feel themselves to be persecuted, or hated and threatened by everyone. These people might also believe in conspiracies, which can result in irrational fear.

During the 1920s, the country experienced a period of paranoia. The trauma of World War I was fresh in people's minds, and many were fearful of ever being threatened in such a way again. This led to a strong fear of the "other." This was expressed in practices such as increased racism (ex. the rise of the Ku Klux Klan) or political intolerance (ex. the Red Scare against communists). This was also expressed through isolationism, as many people believed that by keeping the country free of foreign influence, they would be less threatened by dangerous foreign forces, such as communism.