Been searching for the answer for years. Here goes. B&W movie, made maybe late '40's early '50's. Movie takes place during WWII but is about the impact of the war on our way of life in the U.S. as people have to deal with rationing and the agony of waiting for word from loves ones involved in the war. A recurring theme seems to have been the dark military messenger who would show up in town and everyone feared he would come to their home and bring the grim news of a loved one killed in action. One scene showed characters venting their anger by singing the popular song "Der Fuehrer's Face" with bitter emphasis. Only other thing I can clearly remember is the opening scene: Man is riding on a train and singing a forlorn version of "Happy Days are Here Again". Powerful movie! Don't know why no one remembers it. Please help. (And please don't suggest I am thinking of the animated Donald Duck Short with "Der Fuehrer's Face". This was a full length B&W movie, not a short cartoon.)