There is a large sub-genre called "military sci-fi," with much of what he wants. (https://en.wikipedia.org/wiki/Military_science_fiction https://en.wikipedia.or

There is a large sub-genre called "military sci-fi," with much of what he wants. (https://en.wikipedia.org/wiki/Military_science_fiction https://en.wikipedia.org/wiki/Military_science_fiction) Another area to look is "Victorian sci-fi." (https://www.goodreads.com/shelf/show/victorian-science-fiction https://www.goodreads.com/shelf/show/victorian-science-ficti...)