From a David Weber post to Baen's Bar Honorverse dated July 14, 2006:

Stability of the Republic of Haven and system secession

    The People's Republic of Haven did shed quite a few star systems during its transformation back into the Republic of Haven. It did not lose as many as some of you appear to think it ought to have lost. The reason that I haven't gone into detail about all of this is that some people already think I spent too much time going into detail about political matters and not enough time trying to kill Honor off in a bigger and more glorious death ride.

    In order to understand what happened to the Republic and its membership, you have to remember that Thomas Theisman fought an extensive, multi-sided Civil War against holdouts of the old régime. In other words, there was actual armed conflict, in which the new régime spent treasure and blood evicting the old, terroristic régime of State Security and the Committee of Public Safety. (Can you say "war of liberation"?) Not only that, but as the new régime moved in, it conducted public, honest trials of those accused of committing crimes under the old régime. It offered every star system which had been claimed by the People's Republic (except those still under occupation by the Manticoran Alliance) the right to peacefully opt out the new, restored Republic of Haven. And, as soon as the Constitutional Convention had met and restored the old Constitution, exactly as that Constitution required, the new régime held free and open elections.

    Now, this isn't going to convince every single planet occupied by force by the People's Republic that it wants to remain a part of the new/old/restored Republic of Haven. As I've already said, quite a few of those star systems departed. But go back and look at what Trenis and Lewis have to say after the first series of Cutworm attacks. They say that they have 30 to 35 "first-tier systems," and about that many "second-tier" systems which have to be protected. Do the math. That adds up to about 70 relatively major industrialized systems. Assume another 35 star systems which are industrialized but not net contributors, and another 30 or so which constitute economic sinkholes, and you're up to about 135 systems. There are additional inhabited systems in what used to be the People's Republic whose economies were primarily agrarian or extractive, but which had been grabbed off because of strategic positions were which had simply been original daughter colonies of Haven herself, but not a lot. So, where are all the other 200-plus Peep-controlled star systems? Well, most of the missing members decided to avail themselves of the option to leave the Republic… and were allowed to do so.

    This is one of the reasons why so many neutrals and even some of the Star Kingdom's allies had begun seeing the new régime in a much more favorable light. It was actually doing what it had said it would do… which the Star Kingdom wasn't. Pritchart's position where the Alliance-occupied planets were concerned was predicated on two major concerns, both of which are given in the novel. First, on a pragmatic basis, they represented a strategic threat to the Republic of Haven as long as they remained in the hands of someone who was consistently refusing to negotiate a peace treaty too in the state of hostilities existing between them. Second, she knew that her plebiscites had been honest -- and could demonstrate that they had, both because she'd called in interstellar observers (including observers from other planets considering seceding) and because her government had accepted many plebiscites' results which were not in favor of remaining under her control -- and she didn't trust the High Ridge Government to conduct equally honest votes. And then, on top of everything else, Giancola's manipulation of the diplomatic correspondence between the two nations convinced her that the Star Kingdom had turned expansionist… which was apparently confirmed for all the universe to see when the new Manticoran Grantville Government proceeded to partition Silesia between the Star Kingdom and the Andermani Empire.

    Most of the major economic dynamos of the old Republic of Haven opted to remain in the new Republic of Haven. The majority of them had been Havenite daughter colonies to begin with, although many of them had been independent of the mother world before the original Legislaturalist expansion began. They think of themselves as Havenites, even if they didn't think of themselves as Peeps. Moreover, as I think someone has suggested elsewhere in this thread, the Constitution as restored gives every planet in the Republic proportionate representation in the Havenite Congress.

    Essentially, what happened here is that the People's Republic had extended itself across the total area of its control using the façade of the old Constitution. When Theisman shot Saint-Just, and especially when he brought in a civilian (Eloise Pritchart) with a high reputation as an opponent of the Legislaturalists, and that civilian insisted on a general election as soon as the Constitution was adopted, and invited in interstellar observers of the election process, and what had been the People's Republic of Haven was still officially at war with someone who refused to make peace, who got looked at the good guys? Do you people think that the Republic of Erewhon decided that Eloise Pritchart might be trustworthy after watching her grind the iron heel of the occupying boot down on the neck of star systems trying to leave the Republic, exactly as she'd promised them they could?

    Many of the star systems which did leave the Republic did so with the clear understanding that they would be allowed to rejoin it at a later time if they so chose. And even planets which left the Republic were allowed and invited to participate in the Havenite equivalent of the Marshal Plan as the central government began working on rebuilding hammered economies. Obviously, the war against Manticore has thrown a giant spanner into the works, but there's a reason that people (outside Manticore, at least) are inclined to believe Eloise Pritchart when she says something in the arena of interstellar diplomacy.

    Ultimately, without the war against Manticore, much of the territory lost when star systems exercised the option to secede from what had been the People's Republic of Haven would have returned to the Republic of Haven on a de facto basis, even if those star systems never formally rejoined the Republic. Haven is simply too big, and too powerful economically -- especially once it recovers from its self-inflicted damage -- for it to be any other way. Pritchart and her Cabinet (and her unofficial advisors) were all very well aware of that, and very few of them are idiots. They recognized that any conceivable short-term advantage they might have gotten by forcibly preventing star systems from seceding would have been utterly dwarfed by the long-term advantages of being on good terms with their neighbors and economic partners (or the long-term disadvantages of being on bad terms with them). The Pritchart Administration shaped its policies accordingly, which is precisely what permitted Eloise to retain the biggest, most populous, most economically valuable star systems after the change in management.

    Add to that the fact that most of the "Havenite systems" are convinced that she keeps her word and tells the truth in her diplomacy (which, of course, implies that in this case it's the Manties who must be lying), and that as is observed at least once in the book, there's a powerful sense of the Republic having rehabilitated itself as a major military power after the initial trouncing it gives the Manties, and that there's a tradition of hostility between Haven and Manticore because of the long Cold War between them and the decade and a half of shooting war, and the current war actually enhanced the Republic's stability. Exactly how that may change after the Battle of Manticore remains to be seen, but it was certainly the case going in.

    Now, I could've explained all of us in the book, and eventually you're going to get references to it, but I sort of felt that much of it was implicit in the way that Eloise had expressed her concerns (and the way that other stellar powers clearly regarded her administration), and I was aware of the fact that I was already giving you a lot of political stuff between blowing up starships. So, would you rather have had this little political treatise buried in At All Costs, or not?