War Dogs

Sixty-five years ago today, March 13, 1942, the Department of Defense initiated the "Dogs for Defense" program. Read about it here.
Among the most famous dogs to serve alongside US soldiers was Smoky, a Yorkshire terrier found in a foxhole, and Chips, a highly decorated German Shepard mix.

And in the field of speculative fiction, there's Sergeant Chip, the hero of a story by Bradley Denton. It originally appeared in The Magazine of Fantasy and Science Fiction, but you can read it here.