The youngest US serviceman was 12 year old Calvin Graham, USN. He was wounded in combat and given a Dishonorable Discharge for lying about his age. (His benefits were later restored by act of Congress).
"Vwery interesting!" to quote Artie Johnson
The information about the Graf Spee seems inaccurate, casting doubt on many of the other claims. An Internet search will bring much information about the end of the Graf Spee.
I had some doubts about a few other things as well but have not had the time to confirm or deny.