Good points, Jonathan. The PRH was definitely focusing on mobile units, just like everyone else, once the war began. I'm not sure what the thinking was with regards to Trevor's Star and it's wormhole, though. The security of Trevor's Star, I believe, would be critical to Haven.
The RoH captured San Martin specifically for the economic boost that would have come from possession of the Trevor's Star wormhole. They would have wanted to hold on to it, but wouldn't have expected Manticore to attack through it. As noted earlier, the RoH was expecting to dictate the time and place of the war's opening acts and they were sure Manticore wouldn't.
Once the war started Haven would want to hold on to Trevor's Star for several reasons. One, it's a way to go directly to Manticore and take the fight to the Manti's home system.
Two, if the Manti's get a hold of Trevor's Star it improves the RMN's position tremendously. This is discussed multiple times before the White Haven takes Trevor's Star. The improved logistics and shortcut to the PRH space is a huge benefit to the RMN.
With that in mind, before the war began, I'd have thought that some forts might have been appropriate. (Finances allowing, which I have said I doubted they could cough up the money for.) Once the war began, mining the place and stationing powerful mobile forces to prevent an RMN sally through the wormhole would be the correct action.
Regardless, at the time of HAE, I feel that Trevor's Star would have had to be important to the security of the PRH because of how much possession of it would have helped Manticore.
