I finished this before I looked on the copyright page: it is dated 1999, before the Kris Longknife series started. I originally thought this was written recently as a "back story" novel to that series. Apparently, it is the author's first episode in a series in that universe, one that he subsequently abandoned for the Kris stories, which are set in the same universe, but much later.
That would explain why the Kris stories are better written. This was very entertaining, if you like this type of science fiction, but not as good as the author's later works. I especially had a hard time distinguishing who was on what side in the conflict. Point-of-view switched back and forth without enough cues, for me, to know immediately whose events I was following.
____ possible spoiler _____
A nit about the battles on the airless planetoid that takes up about a third of the novel. It wouldn't have been the same story, of course, but why didn't the attacking force drop a nuke in the middle of the crater rather than land outside and attack the "walls?" Just saying.