[Waverunner]

How about Herbert Hoover and the Boxer Rebellion.
Didn’t he help defend Tsentain, even leading Marines around.
I’m not sure of his military status at the time, but his first national attention was reports of how he used bags of rice to build fortifications to keep the Boxers out of the port town. Keeping the port enabled later relief expeditions to have an easy entry into China.

[Pharmboy]

From what I read in his Wiki bio entry, he never actaully served in the armed forces. During WWI he was involved with humanitarian aid, but no uniformed service.

Thanks for the post, though, after reading his bio, I am impressed.