Welcome to part three where I talk about the other military science fiction series I think are good because I have read them more than once. Again in no particular order of preference:
The Dorsai series by Gordon R. Dickson.I read the original Dorsai trilogy at an early age – and later followed Dickson's expansion of the core books into the Childe Cycle. To brutally honest the expanded universe books do not stand up to repeat readings, but Tactics of Mistake, Soldier Ask Not, and Dorsai! are favourites of mine. There's also Lost Dorsai and The Spirit of the Dorsai, which are two collections of shorts stories and a novella, which are OK, as in worth reading once. However, they share the problem I have with the Childe Cycle of being works where the author's ambition to write about progress versus conservatism resulted in them forgetting that stories have to be interesting beyond the message.
The Posleen series by John Ringo.
The Freehold series by Michael Z. Williamson.
Stark's Crusade trilogy by Jack Campbell.
I have a love hate relationship with the Posleen series by John Ringo, which actually should be called the Aldenata series, but everybody I know who reads these books remembers the Posleen: ravenous aliens that call-back to the Mongol Hordes. However, my love, hate relationship is down to the technology rather than any heavy handed message. I just have a failure to suspend my disbelief when Ringo describes light speed velocity shots being fired inside the Earth's atmosphere. Despite that throwing me out of the world I find myself enjoying the adventures of the various groups, and who can forget the crew of the massive tank called Bun Bun fighting the Posleen with nuclear shells. I also like Tom Kratman's Watch on the Rhine, but it's not to everybody's taste, especially those who don't get black humour.
Freehold is the first book by Michael Z. Williamson, and while the libertarian message is front and centre I can forgive it because the story has characters that one can root for, and the rest of the series: The Weapon, Rogue, and Contact with Chaos are well worth reading; with the latter being particularly good because of its outstanding portrayal of a civilized society restricted by the limitations of resources to stone age technology. In fact I would go so far as to say that the idea of a society restricted by its technology that is forced to work within the limitations of it means is pure SF at its best. I can also recommend his Ripple Creek series for SF private military contractor action.
Finally, Stark's Crusade by Jack Campbell, a pseudonym of John G. Hemry, was an early trilogy of novels written before the Lost Fleet series took off and propelled him into the big league (a definition for this being sells lots of books). Stark's Crusade is the only series of his that I've re-read, which is why it is here in my list. What makes this series stand out for me is the matter of fact way things go wrong in the first novel that marked the stories out as trying to say something different about military operations.