The threats to Midway at the beginning of the book are internal and external: Syndic CEO Boyens' has a fleet hanging out at the hypernet gate. Iceni and Drakon are trying to figure out how to protect their star system, and also to avoid dying at the hands of unknown internal threats. The assumption through most of the book is that the various attempts on the lives and goals of Iceni and Drakon are sponsored by the Syndicate Worlds and/or their Internal Security Forces, the "Snakes". But the character of the attacks suggests otherwise, and eventually, the default assumption is finally questioned by the targets opening their eyes to alternative possibilities.
In choosing to describe a multi-generational war, Campbell took on a task in which it was almost inevitable that everyone would wind up Behaving Very Badly. The initial series, "The Lost Fleet" depicts a Man Out of Time from the beginning of the war, dropped in for a heroic last stand, and then having to deal with the aftermath of a recognizably democratic system that has been perverted in its century plus of warfare. "The Lost Stars" tells the story of the other side: a dictatorial system built upon layers of betrayal and corruption and backstabbing, violent from the top to the bottom. You would think this would be an ugly, horrifying story, but in a lot of ways, it is even more appealing than the first series. It is the story of people who, having identified the worst of the abusers, feel their way, step by step, to a better way of doing things, always at risk of sliding into chaos, and whose programming from birth is to assume the worst in every situation. Needless to say, everyone in the book has done awful things (sometimes to each other); believably describing how people in this situation can find a way to work together cannot have been easy.
I have a weakness for mil sf in which women and men equally hold positions in all areas and at all levels. There are some quirks in Campbell's writing that I don't find particularly believable (if everyone has already forgotten the horse in the "free rein" metaphor, no one is going to be making farm animal analogies in space. Seriously. Altho he does play it for laughs, on occasion: "Get out of Dod".). But I enjoy Campbell's willingness to write complex characters who struggle to negotiate and compromise, yet set limits effectively.