I've never been clear about the proper placement of these.
Should they have a planet in their range? If so, are they more effective around my planets, or around opponents' planets?
Are they effective if a Starbase (mine or opponent) is in range?
Are they more effective if somebody's trade route goes through one?
I'm just trying to figure out how to use these or if they're even worthwhile. It seems almost that military starbases are not effective unless you build a gauntlet of them and force enemy forces to confront nearby fleets and maybe become weakened before getting to a planet that the opponent wants to overtake.