Question: What was the "Hale America" campaign during World War II? 

Answer: In 1942, despite the United States involvement in World War II, President Roosevelt gave baseball the ‘green light’ to continue on. Roosevelt stressed the importance of more night games, allowing war time workers to catch night games at the ball park. In support of America’s efforts throughout World War II, each major league team wore the insignia of the “Hale America” campaign on their jersey.
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