With the US launched into World War II, Hollywood began working with the armed forces to get people to join. An example is John Huston's Academy Award-nominated "Winning Your Wings", featuring Jimmy Stewart talking about the Air Force, the enlistment process, and who all participates in operating the planes.
Obviously the sheer level of propaganda comes across as corny nowadays, especially with the archaic gender relations. My favorite propaganda shorts from the era were the cartoons portraying Bugs Bunny and Daffy Duck battling Nazis (not surprisingly, many of them got pulled from circulation after the war).
Anyway, this short works well as a time capsule. Entertaining, if nothing else.