Answer:
When they started producing propaganda, that infused or controlled people's opinion internally. So Americans became more xenophobic to the Japanese, and the Russians.
Step-by-step explanation:
Back in this era, people lined up for media. I mean they still do know, but tv's weren't in every house. For most who could afford a newspaper could afford, to go see a film. Propaganda was in school, children were prejudice against other children.