Ring of Steel was an Army recruiting film released sometime in the early 1940s and narrated by Spencer Tracy

Spencer Tracy

Spencer Bonaventure Tracy was an American theatrical and film actor, who appeared in 75 films from 1930 to 1967. Tracy was one of the major stars of Hollywood's Golden Age, ranking among the top ten box office draws for almost every year from 1938 to 1951...

. The exact date of the film is not certain: Internet Archive.org

Internet Archive

The Internet Archive is a non-profit digital library with the stated mission of "universal access to all knowledge". It offers permanent storage and access to collections of digitized materials, including websites, music, moving images, and nearly 3 million public domain books. The Internet Archive...

 says 1941, which would explain the lack of any explicit mention of World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, whereas the Internet Movie Database

Internet Movie Database

Internet Movie Database is an online database of information related to movies, television shows, actors, production crew personnel, video games and fictional characters featured in visual entertainment media. It is one of the most popular online entertainment destinations, with over 100 million...

 gives its release date of April 7, 1942.

The film uses stock footage with Tracy's voice-over

Voice-over

Voice-over is a production technique where a voice which is not part of the narrative is used in a radio, television production, filmmaking, theatre, or other presentations...

 narrating the story of America's military history from the perspective of the personification of the American soldier. It starts with Lexington and Concord "Where I was born" through the First World War, listing the US military's achievement and urging young men to sign up.