Frank Sinatra considered Kate Smith the best singer of her time, and said that when he and a million other guys first heard her sing "God Bless America" on the radio, they all pretended to have dust in their eyes as they wiped away a tear or two.
The story behind the first public showing of the song was that the time was 1940. America was still in a terrible economic depression. Hitler was taking over Europe and Americans were afraid we'd have to go to war. It was a time of hardship and worry for most Americans.
This was the era just before TV, when radio shows were HUGE, and American families sat around their radios in the evenings, listening to their favorite entertainers, and no entertainer of that era was bigger than Kate Smith.