Also see A Collection of Unmitigated Pedantry's series of fortifications [0] regarding castles and their strategic importance, especially on how they were essential to local control of the area as opposed to "just" FOBs for military campaigns. (Incidentally the term "tyranny of the wagon equation" linked in the article also eventually leads to a different ACOUP series.)

[0] https://acoup.blog/2021/12/10/collections-fortification-part...